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Chen G

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  1. Like
    Chen G got a reaction from Beerzerker in PSU wattage numbers are nonsense   
    it is single rail, there's no extension, the custom silver cables go straight to the PSU
    yea I know, obviously.
    What I think is happening is the PSUs have over current protection that detect a over current, even just for 5ms (from power spike) and it shuts down the system.
    I just think a bigger PSU will have their protection set at higher current so it won't trip and reboot.
    my original spec if just counting the CPU and GPU, was 120+250=370w, way under the 600w PSU rating. Even adding in RAM and chipset I'm pretty sure I'm under 450w, which is also confirmed by PSU report I got after switching PSU. That's over 25% headroom, and it wasn't enough.
     
    with the 3090 upgrade, I added 100w to the GPU and maybe 10 on SSD. So let's say 560w theoretical, again confirmed from PSU report, that's about as high as it goes, way under 850w PSU, this time with 34% headroom, it wasn't enough.
     
    so I'd say add 50% headroom for spikes.
     

  2. Agree
    Chen G got a reaction from Stahlmann in Get Dolby Vision instead of HDR10 on Windows 10?   
    You're doing something wrong there, that's not supposed to happen.
    The only real meaningful difference between HDR10 and Dolby Vision is... too technical to talk about. Basically you can present dark scenes with less banding, more effective bits to work with.
     
    It's unlikely Windows will support Dolby Vision because it'll mess up the desktop. A much simpler solution is to just run the screen in 12-bit.
  3. Funny
    Chen G got a reaction from Slayerking92 in Lol never buying another Gigabyte MB again   
    Back in 2012, I bought a Gigabyte X79 motherboard, while it kept working and working for a very long time, and it still is working, it had this one quirky bug, to actually boot I must follow this exact procedure:
    Press power button Smash delete to get into BIOS, because otherwise it will fail to boot 100% Choose save and exit, or anything that will make the system reboot Smash delete to get into BIOS again, because again it will not boot if you don't Choose save and exist, again. This time it will boot 100%  Yes I had to follow this procedure for 7 years, it has always worked and failure to do so has never worked. The thing is, this is only required once I overclock beyond a certain point, I believe it was over 3.8Ghz on the 3930k. Anything below or at 3.8Ghz can just boot normally without doing all that stunt, but anything beyond 4Ghz requires it to work. And no, it's not because some settings got reset and I'm booting into the system with stock settings or anything stupid like that, it does run the exact overclock I entered in BIOS, but somehow that stunt just is mandatory. Also it's been 7 years so I know the overclock is stable.
     
    Now I have myself a Gigabyte X570 Aorus Master, I put together this rather complicated build with custom loop and modified case, what do I get? A very similar stupid bug. I think there' just something seriously wrong with Gigabyte's boot firmware. Although quite similar, it isn't exactly the same, I haven't figured out the exact pattern yet but from what I have figured out so far:
    A straight cold boot is 100% fail, Windows boot manager comes up with a blue screen saying some kernel file can't be loaded or something It sometimes will freeze either during the POST logo, or inside the BIOS If I go in the BIOS and just select save and exit, it will almost certainly boot Although it appears that booting does not require two restarts like before, the fact that it can sometimes freeze at the POST screen makes installing and updating Windows a nightmare. What can happen is during a critical boot sequence, like the first boot or first boot after major update, it may fail with that can't find kernel file stuff, and then Windows will thing something went wrong and it won't boot normaly the next time but go to recovery or try to roll back the update, which may also fail and just causing the entire system to be corrupted.
     
    I'm not sure if this time it only happens with overclocking, haven't done enough testing yet. But I do know the freezing in BIOS thing only happens when overcloking, it does not happen with stock settings. But it's not like I have an unstable clock, I'm just using PBO it's not even a manual overclock like the last system. Also It's rock stable once it boots, it's just the POST and boot sequence that's extremely fragile and finicky. 
     
    Between these two boards I used an ASUS Rampage Extreme VI for a year, never had any issues, it ran beautifully, felt a distinct lack of quirky random bugs. Like for example on this x570 BIOS if you go into settings>miscellaneous and back out, the contents of the "settings" category changes, and has 3 more options, which would normally be in different places. What a mess.
  4. Agree
    Chen G got a reaction from BTGbullseye in GPU Tier List?   
    more expensive=better.
    It's not
    It's not 50%
    And it's common to not be able to use all the modules in a chip, you don't use 100% of the CPU either, even when it says 100%, that's just 100% of the execution unit.
  5. Like
    Chen G got a reaction from BiG StroOnZ in Ultra silent build V2   
    So a bit about the specs.
     
    I really had a crush on the ASUS X570 WS board, but I did not end up going that route because I want to put a block on the chipset to get rid of the fan. I had already made another x570 build so I know the fan doesn't really bother anybody at all but still, it's aesthetics. EK only makes blocks for the gigabyte boards so that's what I had use. 
    I picked the X570 Master because it's the only one without display outputs, and I like that, because it's more elegant to just not have something you'll never use anyway.
     
    For storage, I am actually doing a RAID-0 with 2x 970 Pro. I don't think this will give better performance than one PCI-E 4.0 drive, since you are now going through the chipset rather than the CPU. However, I don't like any of the existing PCIE 4.0 drives, they all have silly designs and silly names. Plus they're all TLC or 3D VNAND, not MLC.
     
    The PSU still has a fan on it sure, but I have confirmed that it never actually spins because of the efficiency is so high. The system when gaming operates exactly around peak efficiency of this platinum rated PSU, so that's just perfect. I could go get a Seasonic fanless, but it's a bit cheaper to use the used HX850i I already have.
     
    The GPU is as mentioned, a reference design 2080ti. BTW I like this reference design much better than the non-reference I had las time. That one was much bigger but there were quite a few empty spaces on the board and I don't like that. Much better to have them all cramped on a reference sized PCB, there's a waterblock ontop anyway so thermals isn't a problem. The EKWB block worked like a charm this time, GPU temps is only like 15 degrees higher than water at max load. Where as before it was more like 30 degrees.
     
    Is the full cover monoblock necessary? Oh hell no, in fact I'm not sure it cools better than the stock fin array, because there's like 1cm of metal between the water and the VRM, and it's just flat metal, no water channel. It's just for aesthetics, which I'm kinda glad I did this because the plastic I/O cover conflicts with the radiator and I had to remove it. Without the big monoblock this would look quite sad also without that plastic I/O cover.
     
    The chipset block is also just thick flat metal, so the cooling performance isn't stellar there either, the chipset can get as high as 56 degrees, which is just fine for chips but still, couldn't they at least make the metal thinner?
     

    Here is the RGB
     
    With clear water those lights kinda just goes through and light up the ceiling, which I did not like that much. Having this white/silver stuff in the water really makes the RGB shine, literally. A lot of them stuck to the walls but that kinda works too.
  6. Informative
    Chen G got a reaction from DJ46 in Ultra silent build V2   
    Those are just not the mainstream kind of fabric sleeve, it's a layer of clear teflon coat.
     
    CPU is around 55 for gaming and ~65 fo max load. GPU is just chilling, doesn't even go over 45.
     
    The PSU temp readings don't go above 50, I cannot flip it around for cable management reasons, that would make the back a lot more messy.
  7. Like
    Chen G got a reaction from DJ46 in Ultra silent build V2   
    So a bit about the specs.
     
    I really had a crush on the ASUS X570 WS board, but I did not end up going that route because I want to put a block on the chipset to get rid of the fan. I had already made another x570 build so I know the fan doesn't really bother anybody at all but still, it's aesthetics. EK only makes blocks for the gigabyte boards so that's what I had use. 
    I picked the X570 Master because it's the only one without display outputs, and I like that, because it's more elegant to just not have something you'll never use anyway.
     
    For storage, I am actually doing a RAID-0 with 2x 970 Pro. I don't think this will give better performance than one PCI-E 4.0 drive, since you are now going through the chipset rather than the CPU. However, I don't like any of the existing PCIE 4.0 drives, they all have silly designs and silly names. Plus they're all TLC or 3D VNAND, not MLC.
     
    The PSU still has a fan on it sure, but I have confirmed that it never actually spins because of the efficiency is so high. The system when gaming operates exactly around peak efficiency of this platinum rated PSU, so that's just perfect. I could go get a Seasonic fanless, but it's a bit cheaper to use the used HX850i I already have.
     
    The GPU is as mentioned, a reference design 2080ti. BTW I like this reference design much better than the non-reference I had las time. That one was much bigger but there were quite a few empty spaces on the board and I don't like that. Much better to have them all cramped on a reference sized PCB, there's a waterblock ontop anyway so thermals isn't a problem. The EKWB block worked like a charm this time, GPU temps is only like 15 degrees higher than water at max load. Where as before it was more like 30 degrees.
     
    Is the full cover monoblock necessary? Oh hell no, in fact I'm not sure it cools better than the stock fin array, because there's like 1cm of metal between the water and the VRM, and it's just flat metal, no water channel. It's just for aesthetics, which I'm kinda glad I did this because the plastic I/O cover conflicts with the radiator and I had to remove it. Without the big monoblock this would look quite sad also without that plastic I/O cover.
     
    The chipset block is also just thick flat metal, so the cooling performance isn't stellar there either, the chipset can get as high as 56 degrees, which is just fine for chips but still, couldn't they at least make the metal thinner?
     

    Here is the RGB
     
    With clear water those lights kinda just goes through and light up the ceiling, which I did not like that much. Having this white/silver stuff in the water really makes the RGB shine, literally. A lot of them stuck to the walls but that kinda works too.
  8. Like
    Chen G got a reaction from DJ46 in Ultra silent build V2   
    While I don't really like colour fluids, I thought clear looked boring, so I tried some which didn't work out as I imagined but still somewhat better than totally clear I think...

    Rheoscopic Fluid. You basically just add extremely fine powder in the water, it never dissolves so it makes these swirly patterns.
    It looked really cool at first, and although it doesn't clog or dissolve, it doesn't just stay looking like this either...
     

    It seems to stick to the walls of the loop, so there's less and less of it actually circulating in the water. I didn't want to add more of it because I'm afraid of clogging. But I also didn't try to get rid of them, so I guess we'll see what happens in the long term.

    Last time I got lazy and just used a card that came with a block. It was terrible, there is a huge gap between the GPU and the plate and temps were abysmal until I changed to better paste, it was still not good but at least better than air.
    This time I'm putting on EK blocks myself.

    It just looks like fog/droplets, or probably ice/frost, which is probably a decent effect?
    No, it does not clog at the water channels at all.
     
    Now, fully completed beauty shots:
     





  9. Like
    Chen G got a reaction from Meganter in Ultra silent build V2   
    So a bit about the specs.
     
    I really had a crush on the ASUS X570 WS board, but I did not end up going that route because I want to put a block on the chipset to get rid of the fan. I had already made another x570 build so I know the fan doesn't really bother anybody at all but still, it's aesthetics. EK only makes blocks for the gigabyte boards so that's what I had use. 
    I picked the X570 Master because it's the only one without display outputs, and I like that, because it's more elegant to just not have something you'll never use anyway.
     
    For storage, I am actually doing a RAID-0 with 2x 970 Pro. I don't think this will give better performance than one PCI-E 4.0 drive, since you are now going through the chipset rather than the CPU. However, I don't like any of the existing PCIE 4.0 drives, they all have silly designs and silly names. Plus they're all TLC or 3D VNAND, not MLC.
     
    The PSU still has a fan on it sure, but I have confirmed that it never actually spins because of the efficiency is so high. The system when gaming operates exactly around peak efficiency of this platinum rated PSU, so that's just perfect. I could go get a Seasonic fanless, but it's a bit cheaper to use the used HX850i I already have.
     
    The GPU is as mentioned, a reference design 2080ti. BTW I like this reference design much better than the non-reference I had las time. That one was much bigger but there were quite a few empty spaces on the board and I don't like that. Much better to have them all cramped on a reference sized PCB, there's a waterblock ontop anyway so thermals isn't a problem. The EKWB block worked like a charm this time, GPU temps is only like 15 degrees higher than water at max load. Where as before it was more like 30 degrees.
     
    Is the full cover monoblock necessary? Oh hell no, in fact I'm not sure it cools better than the stock fin array, because there's like 1cm of metal between the water and the VRM, and it's just flat metal, no water channel. It's just for aesthetics, which I'm kinda glad I did this because the plastic I/O cover conflicts with the radiator and I had to remove it. Without the big monoblock this would look quite sad also without that plastic I/O cover.
     
    The chipset block is also just thick flat metal, so the cooling performance isn't stellar there either, the chipset can get as high as 56 degrees, which is just fine for chips but still, couldn't they at least make the metal thinner?
     

    Here is the RGB
     
    With clear water those lights kinda just goes through and light up the ceiling, which I did not like that much. Having this white/silver stuff in the water really makes the RGB shine, literally. A lot of them stuck to the walls but that kinda works too.
  10. Like
    Chen G got a reaction from Meganter in Ultra silent build V2   
    While I don't really like colour fluids, I thought clear looked boring, so I tried some which didn't work out as I imagined but still somewhat better than totally clear I think...

    Rheoscopic Fluid. You basically just add extremely fine powder in the water, it never dissolves so it makes these swirly patterns.
    It looked really cool at first, and although it doesn't clog or dissolve, it doesn't just stay looking like this either...
     

    It seems to stick to the walls of the loop, so there's less and less of it actually circulating in the water. I didn't want to add more of it because I'm afraid of clogging. But I also didn't try to get rid of them, so I guess we'll see what happens in the long term.

    Last time I got lazy and just used a card that came with a block. It was terrible, there is a huge gap between the GPU and the plate and temps were abysmal until I changed to better paste, it was still not good but at least better than air.
    This time I'm putting on EK blocks myself.

    It just looks like fog/droplets, or probably ice/frost, which is probably a decent effect?
    No, it does not clog at the water channels at all.
     
    Now, fully completed beauty shots:
     





  11. Like
    Chen G got a reaction from Meganter in Ultra silent build V2   
    I had a proof of concept silent build which I hacked together with existing and used parts, while it certainly wasn't gehtto, it wasn't as refined as I had hoped. I was able to sell it and recoup almost all my investment, and I tried again.
    This time I am mostly focusing on improving aesthetics, because the cooling and silence already worked pretty well.

    I start with the same Cooler Master SL600M case.
     
     

    Rather than brown Noctua fans, I got black ones this time.
     

    These fans aren't cheap, and they don't make all that much of a difference. However, since these are the ONLY fans that cools everything, it'll still be worth it.
     

    I still wanted to improve cooling so I chose slightly thicker rads, knowing I would have to raise the radiator bracket to make it fit.
     

    However this created an additional problem, I could no longer rely on taping up the radiator bracket to stop air from escaping without going through the radiator, which is absolutely critical to the performance of my design.
     


    Since I don't have a 3D printer, black cardboard will have to do. I am basically cutting out a gasket for the radiator to fit through, sealing all the holes to force as much air as possible through the radiator.
     

    The chosen hardware this time is X570 with 3950x. Having just one CCD would be weird because the other spot is empty. And having one chiplet be like partially disabled would also be kinda weird, so for best aesthetics, I had to choose the 3950x. Although admittedly any disabled chip is aesthetically unsatisfying, like the 2080ti, but the RTX Titan is just too expensive. Plus, the situation is less severe with monolithic dies.
     

  12. Like
    Chen G got a reaction from Rune in Ultra silent build V2   
    I had a proof of concept silent build which I hacked together with existing and used parts, while it certainly wasn't gehtto, it wasn't as refined as I had hoped. I was able to sell it and recoup almost all my investment, and I tried again.
    This time I am mostly focusing on improving aesthetics, because the cooling and silence already worked pretty well.

    I start with the same Cooler Master SL600M case.
     
     

    Rather than brown Noctua fans, I got black ones this time.
     

    These fans aren't cheap, and they don't make all that much of a difference. However, since these are the ONLY fans that cools everything, it'll still be worth it.
     

    I still wanted to improve cooling so I chose slightly thicker rads, knowing I would have to raise the radiator bracket to make it fit.
     

    However this created an additional problem, I could no longer rely on taping up the radiator bracket to stop air from escaping without going through the radiator, which is absolutely critical to the performance of my design.
     


    Since I don't have a 3D printer, black cardboard will have to do. I am basically cutting out a gasket for the radiator to fit through, sealing all the holes to force as much air as possible through the radiator.
     

    The chosen hardware this time is X570 with 3950x. Having just one CCD would be weird because the other spot is empty. And having one chiplet be like partially disabled would also be kinda weird, so for best aesthetics, I had to choose the 3950x. Although admittedly any disabled chip is aesthetically unsatisfying, like the 2080ti, but the RTX Titan is just too expensive. Plus, the situation is less severe with monolithic dies.
     

  13. Informative
    Chen G got a reaction from 69gb in Dare I say it, but I think you're all using fans wrong.   
    People talk about airflow management but I think everyone has been doing this wrong all this time. Conventional wisdoms like mounting fans on radiators, or having exhaust fans etc, it's just wrong and I have a build to prove it:
    Repeating the video description here, the fan speed on this build is controlled by the front panel speed for the demonstration, and it is on MAX SPEED. This is as noisy as it will ever get.
    I'm also not sticking some super lower power stuff in there, what you're looking at is a 7980XE and a 2080TI. Admittedly I am not overclocking the crap out of them but they are running above stock.
    So what about the thermals, am I just constantly butting up against 99 degrees and throttling? Absolutely not, a general figure I can give is 70 degrees maximum for GPU at 500w CPU+GPU power draw at 23 degrees room temperature. CPU thermals will depend on the interface, delid, lapping, LM etc, because that's going to be the biggest bottleneck.
    I'm sure this level of silence and thermal performance can also be done on a huge elaborate loop maybe with dual 480 rads or something. While a loop is required, I am using a pretty basic EKWB kit.
     

     
    To explain what I did here, I'm going to point out the top three problems conventional fan placements have:
     
    1. Wasted airflow. If you get air into your case and it just flows directly back out without cooling anything, you're generating noise for no thermal gains.
    This is extremely common with the standard front intake top exhaust case layout. Think about that top corner, what's going on there? The front fan sucks in air and it immediately goes back out the top, you've basically generated some noise for nothing. 
     
    2. Sub-optimal temperature difference. When air flows past a fin, the amount of heat transfer is determined by the difference in temperature, if you put a radiator at your intake, the air you take in have reduced cooling effect on everything else in the case, this again make you generate more noise with no thermal gains.

    Look at this here, we've got these radiators on the intake, which means your hybrid cooling cards are no longer hybrid they're basically just running on one 120mm rad, because the hot air isn't going to cool the rest of the air cooling heat sinks all that much.
     
    And then look at that traditional read exhaust fan, what's the point of that? Aren't you just sucking cold air out? Wouldn't it be better if all your available air either go through the top radiator or the graphics cards?
     
    3. Aerodynamic disruption. Placing fans right up against something, whether it's a solid piece of glass or a semi-permeable structure like a radiator makes it far less efficient, even for the best fans.
    To see how much of a difference this makes all you have to do is take off one of your fans, turn on the computer, and hold the fan either in open air, or up against its regular position. If you're running any significant fan speeds, the difference will be very noticeable. You're making a lot more noise, but defiantly less air. All those impressive fan specs you see on Noctua's website, well most of those are for open air operation, not up against a radiator.
     
    I basically designed a build specifically to eliminate all of these problems, and there is exactly one case not just compatible, but perfect for what I'm trying to do here:
     
    The Cooler Master SL600M
     
    Now if you read the reviews, you'll notice that it doesn't have the best reviews, a common complaint is high CPU temperatures, which is to be expected, as the graphics card is not only blocking the air path to the CPU, but also pre-heating the air, exacerbating the 2nd problem I mentioned above. However, the solution to that, is just forget about how the air interacts with the parts inside, but focus on the entrance and exit, because those are the spots where we can be certain all the air will have to go through.

    There's two giant 200mm intake fans, so we know air must come in here, and then since the front panel is closed, and there's no exhaust fan on the usual spot, we know the air must exist through the top side, where a radiator mount is conveniently located. At first I still had the traditional mindset of sticking fans on radiators so I had the fans over the radiator to suck out the heat, it worked but noise did not reduce compared to my previous build with the same 360rad and fans.
     
    But then it dawned on me, that there's just no reason to have those fans, if I just seal the case such that all air must escape through the radiator, then I will get an airflow through the radiator because the bottom fans are constantly taking in air, there's no where else for the air to go!

     
    There is actually no attempt from CM to seal the case for this use case, there's a huge gaping hole around the power switch which I had to cover up with cardboard. If I didn't do this none of this would work because the air would just go through those holes rather than through the radiator which has more resistance. There's also the issue of expansion card brackets. Most cards for cooling reasons will put exhaust grids on their brackets, but we can't have that in this build because the air will just escape through those grids rather than through the top radiator.
     
    Now let's look back at our three airflow problems and see how they've been solved:
     
    1. There is no wasted airflow at all, because all air must escape through the top radiator, which cools the CPU and GPU, so we do not generate any unnecessary noise.
    2. The air that gets to the top radiator will barely be carrying any heat because well, the CPU and GPU's heat are in the radiator, so we get maximum heat transfer.
    3. While there is an air filter against the bottom fans, there's basically zero obstruction near the fans, so they can operate very close to their open air performance.
     
    In fact, by doing this with this specific case we get some more additional benefits:
    4. Because the intake fan is 200mm, and max fan speed is only 800RPM, the noise to airflow ratio is extremely high and unmatched by any 120mm or 140mm fan.
    6. Because of the huge intake area of 2x200mm fans, intake airspeed is very low. Not only does this mean low noise, it also sucks in less dust/particles. the filter doesn't need to be cleaned for at least half a year or more.
    7. There's only two fans in the system (the one 120mm you see behind the panel is for back-up when the side panel is open), and it is extremely easy to set up an almost ideal fan curve to further minimize dust build-up (because noise is already minimal). I just stick a thermal probe in the radiator (or if you want to be fancy, a water temperature probe), and all you need to do is change the fan speed with the water temperature. You get an extremely gradual ramp, and you get exactly what your system needs for keeping cool.

     
    Again, this is at max fan speeds, and I'm placing the phone right against the exhaust port. You can see on the graph the noise peak is at ~150hz, a very subtle low frequency humm, if you have good enough ears to even hear it.
     

     
    The main reason most DIY cases don't do this is probably the requirement on sealing. The approach is actually not uncommon with purpose designed machines like this Mac Pro. While it doesn't have a water loop, there's similarly no fan on the CPU or GPU heat sinks. Instead the fans are at the front, which gets tunnelled to the heatsinks. This way you don't reduce the efficiency of your fans.
    Other examples of this are the trash can Mac Pro, and the new Xbox Series X, the ideas are the same. You somehow make a tunnel with all your heatsinks inside, and all you have to do is put one fan at the start or end of the tunnel to cool everything in the tunnel. No wasted airflow, and your heatsinks always get the coldest air possible. Could even take some slight advantage of the chimney effect.
     

     
    This is an experimental build I just made, while the thermal and acoustic performance of this is nowhere near as good as the big build. To my defence, there is only room for a 120mm rad and this machine, and despite being ITX, I think is as good as any full sized build with 120mm AIO. The airflow is less clean on this, but there's still no fan on the AIO radiator, the air pressure will find its way out of the system so it doesn't need to be linear.

    So Again I've completely sealed the case with packing tape, except for the 120mm AIO radiator, and the exhaust port of the blower 5700xt. Yes the blower 5700XT, and I actually specifically picked the blower because the regular third party rack cooler design would just allow air to escape through the rear bracket without passing through much of the GPU's heatsink. The 2 140mm RGB fans are both intake, and once the air gets in, they can only escape either through the GPU blower, or the CPU radiator.
     
    This is ITX and I'm working with only 2 140mm fans but thermals/noise efficiency is actually better than open air. And the reason is quite simple, I am effectively using 2x 140mm fans to push one blower 5700xt and one 120mm radiator. If it was just open air, I'd only have 1x 120mm and 1x ~50mm fan to do the same thing. So another way to think about this approach, is it allows you to mount more or bigger fans on your radiator than you other wise could, and run those fans at increased efficiency.
     
    The interesting thing is I got this case second hand, and the original owner gave me a mesh side panel and told me to use that to improve thermals. The fact that Phanteks sells that just means most builds in this case have worse thermals than open air. Also just from watching Gamer's Nexus, I get the impression that the accepted norm is that almost any case is not as good as open air. However by actually using fans correctly here, I have somehow achieved better than open air performance in an ITX case. Of course it won't beat a proper third-party rack cooler plus bigger AIO on open air, but that's not the point.
     
    I'm not trying to pick on anybody here, it's a sick build I love it but I'm just taking a random example to illustrate the problem.
    So he's got a radiator on the intake, which seems to be quite common now days. Provided the CPU isn't that hot so the pre-warming effect won't be too significant, the GPU is air cooled so it still has to work extra hard than if the radiator was at the exhaust. Just this one placement difference reduces the thermal/noise efficiency of your GPU.  There's three exhaust fans up top but they're too far away to be sucking the GPU's exhaust out so I'd guess they're sucking out a lot of the air from the radiator, but since your CPU is so efficient, you're moving a lot of air to cool a not very hot CPU, wasting existing airflow capability.
    Another stunning build, but this dual rad on both intake/exhaust layout is also pretty common and it doesn't maximize thermal/noise efficiency. The first obvious problem is fans against the radiator, so i already talked about that. But then if we think about this, you are basically taking the exhaust air of the first rad into the case, which is bad for the passively cooled components, and then you run that through the second rad, which will be no where near as efficient as the first one, but it costs just as much and generates just as much noise? 
    I'm not sure how much I can do better with a traditional case like this, because this is definitely partially the case's fault, there's really no room to mount unobstructed fans other than the traditional exhaust spot, which is not only unnecessary but counter productive since again, you'd rather have more air go through your radiators than through nothing. I guess what I would do here is just have one radiator as before, remove the fans, and put all other fans on intake, but then there's no dust filter on some of these so that's gonna be much harder to maintain.
     
    This looks psychedelic and interesting, but there's just massive inefficiency going on here, a lot of air will escape before they even get a chance to touch anything, especially through that top hole, And even if that was filled with a 360 rad instead it's not much help because the air through that fan will have generated the noise of 2 120mm fans, but without cooling much of anything except 1/3 of your CPU.
     
    Looking at all these builds here, I realize mine is seriously lacking in aesthetics, and that's going to be the focus point of mk.2 I am currently planning. No more cheap EK kits and industrial black tubes, this time I'll be using full EK Quantum line of parts. However I am in a big bind here, there's no way I'm going to buy another 2080ti at this point, so most likely the build won't be finished until next-gen GPUs come out, until then I'll probably just run some generic card with stock cooler, it won't look very impressive. I also haven't decided on if I wanna do hard tube, while that looks good it'll be such a pain to change anything, like for example upgrade the CPU.
     
    In terms of cooling, it'll mostly be the same as before, single 360mm rad. While there is space on the bottom intake for radiators, like some builds have done, I don't think I'll actually do that because I think that will give me overall worse thermal/noise ratio because I won't be able to use the 200mm fans. Unless I just stick a thin 360 rad over the 200mm fans, but then I might as well just make the top radiator thicker, it's effectively the same thing, which is exactly what I'm going to do. Instead of the old 38mm rad on top, I'm ordering a 45mm rad. Now there's technically no room but I found the radiator rack can be raised and not interfere with the outer cosmetic shell. So I'm going to just use some MB standoffs to raise the radiator further up so it can be thicker. The bottom panel above the fans will now be filled with the flat radiator I really really love, and hopefully it'll cover up the ugly I/O and fan headers at the bottom of the MB.
     
    =======================
     
    There's an additional complication with the 2nd problem with conventional fan placement I mentioned towards the beginning. That is, paradoxically, stronger cooling is less efficient.
    What do I mean by this? Well think of a given CPU cooler and air flowing past it, if the flow is constant, the amount of thermal transfer happening here is NOT constant, it depends on the temperature difference between the air and the cooling fins. This means the hotter the fins, the more cooling you can do, and this usually means higher CPU temperatures. Therefore, in reverse, if you have a big 360mm rad on your 65w CPU, and it's 55 degrees under load, all that means is you are pushing a lot more air to cool 65w, than if the radiator was 120mm and the CPU is say, 75 degrees under load. Basically, you need exponentially more airflow (and therefore noise) to cool the same thermal power, if you want to keep your heatsinks cool.
     
    There is a way around this, and that's to reduce the temperature delta between the cooling fins and the thing you're trying to cool, it works because you aren't changing the temperature of your cooling fins, so you maintain the same amount of heat transfer between the fins and air, but you still make what you're trying to cool, cooler.
     
    So for the efficiency minded builder, you need to keep your priorities straight:
     
    1. Do not try to achieve unnecessarily low temperatures, cooling fetish is a real thing but you gotta remember the reduction in performance is exponential as your heat sink gets cooler. Just what kind of temperatures are good well that's a whole new can of worms we won't get into here.
    2. First thing you do to improve cooling is to improve the thermal interface, better paste, liquid metal, delid, lapping etc... Because these methods of reducing temperature are "free" and don't require more air flow / noise. This is one of the reasons why water cooling is so ridiculously good, you can minimize the temperature delta between lots and lots of cooling fins, and your CPU. Where as an air cooler's fins get colder very quick as they get more distant from the CPU.
    3. Increasing surface area of cooling fins. Air is just the worst at conducting heat, so a few millimetres between two cooling fins usually means there's like 1 millimetre of air in the middle that's not getting any heat transfer. So even with the same amount of flow, there's usually ways to dump more heat into it before the air leaves. This could mean denser fins, thicker rads, bigger rads, those all have their own pros and cons obviously, but find ways to dump more heat into the same amount of air. Average temperature of all the exhaust gas should ideally be as high as possible, that's a sign of an efficient cooling system.
    4. Increasing airflow should always be the last resort. Higher fan speed is less efficient, more flow separation, more vibration, more noise, but not as much more airflow. More speed also means the air has less time to contact the fins, less heat transfer per unit volume of air. The ideal situation you want to have is a big radiator at high temperatures, and a uniform, slow airflow through it. Not a jet engine with a small heat sink inside.
     
  14. Like
    Chen G got a reaction from Adashmada in Dare I say it, but I think you're all using fans wrong.   
    People talk about airflow management but I think everyone has been doing this wrong all this time. Conventional wisdoms like mounting fans on radiators, or having exhaust fans etc, it's just wrong and I have a build to prove it:
    Repeating the video description here, the fan speed on this build is controlled by the front panel speed for the demonstration, and it is on MAX SPEED. This is as noisy as it will ever get.
    I'm also not sticking some super lower power stuff in there, what you're looking at is a 7980XE and a 2080TI. Admittedly I am not overclocking the crap out of them but they are running above stock.
    So what about the thermals, am I just constantly butting up against 99 degrees and throttling? Absolutely not, a general figure I can give is 70 degrees maximum for GPU at 500w CPU+GPU power draw at 23 degrees room temperature. CPU thermals will depend on the interface, delid, lapping, LM etc, because that's going to be the biggest bottleneck.
    I'm sure this level of silence and thermal performance can also be done on a huge elaborate loop maybe with dual 480 rads or something. While a loop is required, I am using a pretty basic EKWB kit.
     

     
    To explain what I did here, I'm going to point out the top three problems conventional fan placements have:
     
    1. Wasted airflow. If you get air into your case and it just flows directly back out without cooling anything, you're generating noise for no thermal gains.
    This is extremely common with the standard front intake top exhaust case layout. Think about that top corner, what's going on there? The front fan sucks in air and it immediately goes back out the top, you've basically generated some noise for nothing. 
     
    2. Sub-optimal temperature difference. When air flows past a fin, the amount of heat transfer is determined by the difference in temperature, if you put a radiator at your intake, the air you take in have reduced cooling effect on everything else in the case, this again make you generate more noise with no thermal gains.

    Look at this here, we've got these radiators on the intake, which means your hybrid cooling cards are no longer hybrid they're basically just running on one 120mm rad, because the hot air isn't going to cool the rest of the air cooling heat sinks all that much.
     
    And then look at that traditional read exhaust fan, what's the point of that? Aren't you just sucking cold air out? Wouldn't it be better if all your available air either go through the top radiator or the graphics cards?
     
    3. Aerodynamic disruption. Placing fans right up against something, whether it's a solid piece of glass or a semi-permeable structure like a radiator makes it far less efficient, even for the best fans.
    To see how much of a difference this makes all you have to do is take off one of your fans, turn on the computer, and hold the fan either in open air, or up against its regular position. If you're running any significant fan speeds, the difference will be very noticeable. You're making a lot more noise, but defiantly less air. All those impressive fan specs you see on Noctua's website, well most of those are for open air operation, not up against a radiator.
     
    I basically designed a build specifically to eliminate all of these problems, and there is exactly one case not just compatible, but perfect for what I'm trying to do here:
     
    The Cooler Master SL600M
     
    Now if you read the reviews, you'll notice that it doesn't have the best reviews, a common complaint is high CPU temperatures, which is to be expected, as the graphics card is not only blocking the air path to the CPU, but also pre-heating the air, exacerbating the 2nd problem I mentioned above. However, the solution to that, is just forget about how the air interacts with the parts inside, but focus on the entrance and exit, because those are the spots where we can be certain all the air will have to go through.

    There's two giant 200mm intake fans, so we know air must come in here, and then since the front panel is closed, and there's no exhaust fan on the usual spot, we know the air must exist through the top side, where a radiator mount is conveniently located. At first I still had the traditional mindset of sticking fans on radiators so I had the fans over the radiator to suck out the heat, it worked but noise did not reduce compared to my previous build with the same 360rad and fans.
     
    But then it dawned on me, that there's just no reason to have those fans, if I just seal the case such that all air must escape through the radiator, then I will get an airflow through the radiator because the bottom fans are constantly taking in air, there's no where else for the air to go!

     
    There is actually no attempt from CM to seal the case for this use case, there's a huge gaping hole around the power switch which I had to cover up with cardboard. If I didn't do this none of this would work because the air would just go through those holes rather than through the radiator which has more resistance. There's also the issue of expansion card brackets. Most cards for cooling reasons will put exhaust grids on their brackets, but we can't have that in this build because the air will just escape through those grids rather than through the top radiator.
     
    Now let's look back at our three airflow problems and see how they've been solved:
     
    1. There is no wasted airflow at all, because all air must escape through the top radiator, which cools the CPU and GPU, so we do not generate any unnecessary noise.
    2. The air that gets to the top radiator will barely be carrying any heat because well, the CPU and GPU's heat are in the radiator, so we get maximum heat transfer.
    3. While there is an air filter against the bottom fans, there's basically zero obstruction near the fans, so they can operate very close to their open air performance.
     
    In fact, by doing this with this specific case we get some more additional benefits:
    4. Because the intake fan is 200mm, and max fan speed is only 800RPM, the noise to airflow ratio is extremely high and unmatched by any 120mm or 140mm fan.
    6. Because of the huge intake area of 2x200mm fans, intake airspeed is very low. Not only does this mean low noise, it also sucks in less dust/particles. the filter doesn't need to be cleaned for at least half a year or more.
    7. There's only two fans in the system (the one 120mm you see behind the panel is for back-up when the side panel is open), and it is extremely easy to set up an almost ideal fan curve to further minimize dust build-up (because noise is already minimal). I just stick a thermal probe in the radiator (or if you want to be fancy, a water temperature probe), and all you need to do is change the fan speed with the water temperature. You get an extremely gradual ramp, and you get exactly what your system needs for keeping cool.

     
    Again, this is at max fan speeds, and I'm placing the phone right against the exhaust port. You can see on the graph the noise peak is at ~150hz, a very subtle low frequency humm, if you have good enough ears to even hear it.
     

     
    The main reason most DIY cases don't do this is probably the requirement on sealing. The approach is actually not uncommon with purpose designed machines like this Mac Pro. While it doesn't have a water loop, there's similarly no fan on the CPU or GPU heat sinks. Instead the fans are at the front, which gets tunnelled to the heatsinks. This way you don't reduce the efficiency of your fans.
    Other examples of this are the trash can Mac Pro, and the new Xbox Series X, the ideas are the same. You somehow make a tunnel with all your heatsinks inside, and all you have to do is put one fan at the start or end of the tunnel to cool everything in the tunnel. No wasted airflow, and your heatsinks always get the coldest air possible. Could even take some slight advantage of the chimney effect.
     

     
    This is an experimental build I just made, while the thermal and acoustic performance of this is nowhere near as good as the big build. To my defence, there is only room for a 120mm rad and this machine, and despite being ITX, I think is as good as any full sized build with 120mm AIO. The airflow is less clean on this, but there's still no fan on the AIO radiator, the air pressure will find its way out of the system so it doesn't need to be linear.

    So Again I've completely sealed the case with packing tape, except for the 120mm AIO radiator, and the exhaust port of the blower 5700xt. Yes the blower 5700XT, and I actually specifically picked the blower because the regular third party rack cooler design would just allow air to escape through the rear bracket without passing through much of the GPU's heatsink. The 2 140mm RGB fans are both intake, and once the air gets in, they can only escape either through the GPU blower, or the CPU radiator.
     
    This is ITX and I'm working with only 2 140mm fans but thermals/noise efficiency is actually better than open air. And the reason is quite simple, I am effectively using 2x 140mm fans to push one blower 5700xt and one 120mm radiator. If it was just open air, I'd only have 1x 120mm and 1x ~50mm fan to do the same thing. So another way to think about this approach, is it allows you to mount more or bigger fans on your radiator than you other wise could, and run those fans at increased efficiency.
     
    The interesting thing is I got this case second hand, and the original owner gave me a mesh side panel and told me to use that to improve thermals. The fact that Phanteks sells that just means most builds in this case have worse thermals than open air. Also just from watching Gamer's Nexus, I get the impression that the accepted norm is that almost any case is not as good as open air. However by actually using fans correctly here, I have somehow achieved better than open air performance in an ITX case. Of course it won't beat a proper third-party rack cooler plus bigger AIO on open air, but that's not the point.
     
    I'm not trying to pick on anybody here, it's a sick build I love it but I'm just taking a random example to illustrate the problem.
    So he's got a radiator on the intake, which seems to be quite common now days. Provided the CPU isn't that hot so the pre-warming effect won't be too significant, the GPU is air cooled so it still has to work extra hard than if the radiator was at the exhaust. Just this one placement difference reduces the thermal/noise efficiency of your GPU.  There's three exhaust fans up top but they're too far away to be sucking the GPU's exhaust out so I'd guess they're sucking out a lot of the air from the radiator, but since your CPU is so efficient, you're moving a lot of air to cool a not very hot CPU, wasting existing airflow capability.
    Another stunning build, but this dual rad on both intake/exhaust layout is also pretty common and it doesn't maximize thermal/noise efficiency. The first obvious problem is fans against the radiator, so i already talked about that. But then if we think about this, you are basically taking the exhaust air of the first rad into the case, which is bad for the passively cooled components, and then you run that through the second rad, which will be no where near as efficient as the first one, but it costs just as much and generates just as much noise? 
    I'm not sure how much I can do better with a traditional case like this, because this is definitely partially the case's fault, there's really no room to mount unobstructed fans other than the traditional exhaust spot, which is not only unnecessary but counter productive since again, you'd rather have more air go through your radiators than through nothing. I guess what I would do here is just have one radiator as before, remove the fans, and put all other fans on intake, but then there's no dust filter on some of these so that's gonna be much harder to maintain.
     
    This looks psychedelic and interesting, but there's just massive inefficiency going on here, a lot of air will escape before they even get a chance to touch anything, especially through that top hole, And even if that was filled with a 360 rad instead it's not much help because the air through that fan will have generated the noise of 2 120mm fans, but without cooling much of anything except 1/3 of your CPU.
     
    Looking at all these builds here, I realize mine is seriously lacking in aesthetics, and that's going to be the focus point of mk.2 I am currently planning. No more cheap EK kits and industrial black tubes, this time I'll be using full EK Quantum line of parts. However I am in a big bind here, there's no way I'm going to buy another 2080ti at this point, so most likely the build won't be finished until next-gen GPUs come out, until then I'll probably just run some generic card with stock cooler, it won't look very impressive. I also haven't decided on if I wanna do hard tube, while that looks good it'll be such a pain to change anything, like for example upgrade the CPU.
     
    In terms of cooling, it'll mostly be the same as before, single 360mm rad. While there is space on the bottom intake for radiators, like some builds have done, I don't think I'll actually do that because I think that will give me overall worse thermal/noise ratio because I won't be able to use the 200mm fans. Unless I just stick a thin 360 rad over the 200mm fans, but then I might as well just make the top radiator thicker, it's effectively the same thing, which is exactly what I'm going to do. Instead of the old 38mm rad on top, I'm ordering a 45mm rad. Now there's technically no room but I found the radiator rack can be raised and not interfere with the outer cosmetic shell. So I'm going to just use some MB standoffs to raise the radiator further up so it can be thicker. The bottom panel above the fans will now be filled with the flat radiator I really really love, and hopefully it'll cover up the ugly I/O and fan headers at the bottom of the MB.
     
    =======================
     
    There's an additional complication with the 2nd problem with conventional fan placement I mentioned towards the beginning. That is, paradoxically, stronger cooling is less efficient.
    What do I mean by this? Well think of a given CPU cooler and air flowing past it, if the flow is constant, the amount of thermal transfer happening here is NOT constant, it depends on the temperature difference between the air and the cooling fins. This means the hotter the fins, the more cooling you can do, and this usually means higher CPU temperatures. Therefore, in reverse, if you have a big 360mm rad on your 65w CPU, and it's 55 degrees under load, all that means is you are pushing a lot more air to cool 65w, than if the radiator was 120mm and the CPU is say, 75 degrees under load. Basically, you need exponentially more airflow (and therefore noise) to cool the same thermal power, if you want to keep your heatsinks cool.
     
    There is a way around this, and that's to reduce the temperature delta between the cooling fins and the thing you're trying to cool, it works because you aren't changing the temperature of your cooling fins, so you maintain the same amount of heat transfer between the fins and air, but you still make what you're trying to cool, cooler.
     
    So for the efficiency minded builder, you need to keep your priorities straight:
     
    1. Do not try to achieve unnecessarily low temperatures, cooling fetish is a real thing but you gotta remember the reduction in performance is exponential as your heat sink gets cooler. Just what kind of temperatures are good well that's a whole new can of worms we won't get into here.
    2. First thing you do to improve cooling is to improve the thermal interface, better paste, liquid metal, delid, lapping etc... Because these methods of reducing temperature are "free" and don't require more air flow / noise. This is one of the reasons why water cooling is so ridiculously good, you can minimize the temperature delta between lots and lots of cooling fins, and your CPU. Where as an air cooler's fins get colder very quick as they get more distant from the CPU.
    3. Increasing surface area of cooling fins. Air is just the worst at conducting heat, so a few millimetres between two cooling fins usually means there's like 1 millimetre of air in the middle that's not getting any heat transfer. So even with the same amount of flow, there's usually ways to dump more heat into it before the air leaves. This could mean denser fins, thicker rads, bigger rads, those all have their own pros and cons obviously, but find ways to dump more heat into the same amount of air. Average temperature of all the exhaust gas should ideally be as high as possible, that's a sign of an efficient cooling system.
    4. Increasing airflow should always be the last resort. Higher fan speed is less efficient, more flow separation, more vibration, more noise, but not as much more airflow. More speed also means the air has less time to contact the fins, less heat transfer per unit volume of air. The ideal situation you want to have is a big radiator at high temperatures, and a uniform, slow airflow through it. Not a jet engine with a small heat sink inside.
     
  15. Like
    Chen G got a reaction from BHBmods in iPredator Powder - All-in-one-custom-loop   
    Extremely cool but a PCIE extension that long can't be healthy...
  16. Like
    Chen G got a reaction from Windows9 in Dare I say it, but I think you're all using fans wrong.   
    People talk about airflow management but I think everyone has been doing this wrong all this time. Conventional wisdoms like mounting fans on radiators, or having exhaust fans etc, it's just wrong and I have a build to prove it:
    Repeating the video description here, the fan speed on this build is controlled by the front panel speed for the demonstration, and it is on MAX SPEED. This is as noisy as it will ever get.
    I'm also not sticking some super lower power stuff in there, what you're looking at is a 7980XE and a 2080TI. Admittedly I am not overclocking the crap out of them but they are running above stock.
    So what about the thermals, am I just constantly butting up against 99 degrees and throttling? Absolutely not, a general figure I can give is 70 degrees maximum for GPU at 500w CPU+GPU power draw at 23 degrees room temperature. CPU thermals will depend on the interface, delid, lapping, LM etc, because that's going to be the biggest bottleneck.
    I'm sure this level of silence and thermal performance can also be done on a huge elaborate loop maybe with dual 480 rads or something. While a loop is required, I am using a pretty basic EKWB kit.
     

     
    To explain what I did here, I'm going to point out the top three problems conventional fan placements have:
     
    1. Wasted airflow. If you get air into your case and it just flows directly back out without cooling anything, you're generating noise for no thermal gains.
    This is extremely common with the standard front intake top exhaust case layout. Think about that top corner, what's going on there? The front fan sucks in air and it immediately goes back out the top, you've basically generated some noise for nothing. 
     
    2. Sub-optimal temperature difference. When air flows past a fin, the amount of heat transfer is determined by the difference in temperature, if you put a radiator at your intake, the air you take in have reduced cooling effect on everything else in the case, this again make you generate more noise with no thermal gains.

    Look at this here, we've got these radiators on the intake, which means your hybrid cooling cards are no longer hybrid they're basically just running on one 120mm rad, because the hot air isn't going to cool the rest of the air cooling heat sinks all that much.
     
    And then look at that traditional read exhaust fan, what's the point of that? Aren't you just sucking cold air out? Wouldn't it be better if all your available air either go through the top radiator or the graphics cards?
     
    3. Aerodynamic disruption. Placing fans right up against something, whether it's a solid piece of glass or a semi-permeable structure like a radiator makes it far less efficient, even for the best fans.
    To see how much of a difference this makes all you have to do is take off one of your fans, turn on the computer, and hold the fan either in open air, or up against its regular position. If you're running any significant fan speeds, the difference will be very noticeable. You're making a lot more noise, but defiantly less air. All those impressive fan specs you see on Noctua's website, well most of those are for open air operation, not up against a radiator.
     
    I basically designed a build specifically to eliminate all of these problems, and there is exactly one case not just compatible, but perfect for what I'm trying to do here:
     
    The Cooler Master SL600M
     
    Now if you read the reviews, you'll notice that it doesn't have the best reviews, a common complaint is high CPU temperatures, which is to be expected, as the graphics card is not only blocking the air path to the CPU, but also pre-heating the air, exacerbating the 2nd problem I mentioned above. However, the solution to that, is just forget about how the air interacts with the parts inside, but focus on the entrance and exit, because those are the spots where we can be certain all the air will have to go through.

    There's two giant 200mm intake fans, so we know air must come in here, and then since the front panel is closed, and there's no exhaust fan on the usual spot, we know the air must exist through the top side, where a radiator mount is conveniently located. At first I still had the traditional mindset of sticking fans on radiators so I had the fans over the radiator to suck out the heat, it worked but noise did not reduce compared to my previous build with the same 360rad and fans.
     
    But then it dawned on me, that there's just no reason to have those fans, if I just seal the case such that all air must escape through the radiator, then I will get an airflow through the radiator because the bottom fans are constantly taking in air, there's no where else for the air to go!

     
    There is actually no attempt from CM to seal the case for this use case, there's a huge gaping hole around the power switch which I had to cover up with cardboard. If I didn't do this none of this would work because the air would just go through those holes rather than through the radiator which has more resistance. There's also the issue of expansion card brackets. Most cards for cooling reasons will put exhaust grids on their brackets, but we can't have that in this build because the air will just escape through those grids rather than through the top radiator.
     
    Now let's look back at our three airflow problems and see how they've been solved:
     
    1. There is no wasted airflow at all, because all air must escape through the top radiator, which cools the CPU and GPU, so we do not generate any unnecessary noise.
    2. The air that gets to the top radiator will barely be carrying any heat because well, the CPU and GPU's heat are in the radiator, so we get maximum heat transfer.
    3. While there is an air filter against the bottom fans, there's basically zero obstruction near the fans, so they can operate very close to their open air performance.
     
    In fact, by doing this with this specific case we get some more additional benefits:
    4. Because the intake fan is 200mm, and max fan speed is only 800RPM, the noise to airflow ratio is extremely high and unmatched by any 120mm or 140mm fan.
    6. Because of the huge intake area of 2x200mm fans, intake airspeed is very low. Not only does this mean low noise, it also sucks in less dust/particles. the filter doesn't need to be cleaned for at least half a year or more.
    7. There's only two fans in the system (the one 120mm you see behind the panel is for back-up when the side panel is open), and it is extremely easy to set up an almost ideal fan curve to further minimize dust build-up (because noise is already minimal). I just stick a thermal probe in the radiator (or if you want to be fancy, a water temperature probe), and all you need to do is change the fan speed with the water temperature. You get an extremely gradual ramp, and you get exactly what your system needs for keeping cool.

     
    Again, this is at max fan speeds, and I'm placing the phone right against the exhaust port. You can see on the graph the noise peak is at ~150hz, a very subtle low frequency humm, if you have good enough ears to even hear it.
     

     
    The main reason most DIY cases don't do this is probably the requirement on sealing. The approach is actually not uncommon with purpose designed machines like this Mac Pro. While it doesn't have a water loop, there's similarly no fan on the CPU or GPU heat sinks. Instead the fans are at the front, which gets tunnelled to the heatsinks. This way you don't reduce the efficiency of your fans.
    Other examples of this are the trash can Mac Pro, and the new Xbox Series X, the ideas are the same. You somehow make a tunnel with all your heatsinks inside, and all you have to do is put one fan at the start or end of the tunnel to cool everything in the tunnel. No wasted airflow, and your heatsinks always get the coldest air possible. Could even take some slight advantage of the chimney effect.
     

     
    This is an experimental build I just made, while the thermal and acoustic performance of this is nowhere near as good as the big build. To my defence, there is only room for a 120mm rad and this machine, and despite being ITX, I think is as good as any full sized build with 120mm AIO. The airflow is less clean on this, but there's still no fan on the AIO radiator, the air pressure will find its way out of the system so it doesn't need to be linear.

    So Again I've completely sealed the case with packing tape, except for the 120mm AIO radiator, and the exhaust port of the blower 5700xt. Yes the blower 5700XT, and I actually specifically picked the blower because the regular third party rack cooler design would just allow air to escape through the rear bracket without passing through much of the GPU's heatsink. The 2 140mm RGB fans are both intake, and once the air gets in, they can only escape either through the GPU blower, or the CPU radiator.
     
    This is ITX and I'm working with only 2 140mm fans but thermals/noise efficiency is actually better than open air. And the reason is quite simple, I am effectively using 2x 140mm fans to push one blower 5700xt and one 120mm radiator. If it was just open air, I'd only have 1x 120mm and 1x ~50mm fan to do the same thing. So another way to think about this approach, is it allows you to mount more or bigger fans on your radiator than you other wise could, and run those fans at increased efficiency.
     
    The interesting thing is I got this case second hand, and the original owner gave me a mesh side panel and told me to use that to improve thermals. The fact that Phanteks sells that just means most builds in this case have worse thermals than open air. Also just from watching Gamer's Nexus, I get the impression that the accepted norm is that almost any case is not as good as open air. However by actually using fans correctly here, I have somehow achieved better than open air performance in an ITX case. Of course it won't beat a proper third-party rack cooler plus bigger AIO on open air, but that's not the point.
     
    I'm not trying to pick on anybody here, it's a sick build I love it but I'm just taking a random example to illustrate the problem.
    So he's got a radiator on the intake, which seems to be quite common now days. Provided the CPU isn't that hot so the pre-warming effect won't be too significant, the GPU is air cooled so it still has to work extra hard than if the radiator was at the exhaust. Just this one placement difference reduces the thermal/noise efficiency of your GPU.  There's three exhaust fans up top but they're too far away to be sucking the GPU's exhaust out so I'd guess they're sucking out a lot of the air from the radiator, but since your CPU is so efficient, you're moving a lot of air to cool a not very hot CPU, wasting existing airflow capability.
    Another stunning build, but this dual rad on both intake/exhaust layout is also pretty common and it doesn't maximize thermal/noise efficiency. The first obvious problem is fans against the radiator, so i already talked about that. But then if we think about this, you are basically taking the exhaust air of the first rad into the case, which is bad for the passively cooled components, and then you run that through the second rad, which will be no where near as efficient as the first one, but it costs just as much and generates just as much noise? 
    I'm not sure how much I can do better with a traditional case like this, because this is definitely partially the case's fault, there's really no room to mount unobstructed fans other than the traditional exhaust spot, which is not only unnecessary but counter productive since again, you'd rather have more air go through your radiators than through nothing. I guess what I would do here is just have one radiator as before, remove the fans, and put all other fans on intake, but then there's no dust filter on some of these so that's gonna be much harder to maintain.
     
    This looks psychedelic and interesting, but there's just massive inefficiency going on here, a lot of air will escape before they even get a chance to touch anything, especially through that top hole, And even if that was filled with a 360 rad instead it's not much help because the air through that fan will have generated the noise of 2 120mm fans, but without cooling much of anything except 1/3 of your CPU.
     
    Looking at all these builds here, I realize mine is seriously lacking in aesthetics, and that's going to be the focus point of mk.2 I am currently planning. No more cheap EK kits and industrial black tubes, this time I'll be using full EK Quantum line of parts. However I am in a big bind here, there's no way I'm going to buy another 2080ti at this point, so most likely the build won't be finished until next-gen GPUs come out, until then I'll probably just run some generic card with stock cooler, it won't look very impressive. I also haven't decided on if I wanna do hard tube, while that looks good it'll be such a pain to change anything, like for example upgrade the CPU.
     
    In terms of cooling, it'll mostly be the same as before, single 360mm rad. While there is space on the bottom intake for radiators, like some builds have done, I don't think I'll actually do that because I think that will give me overall worse thermal/noise ratio because I won't be able to use the 200mm fans. Unless I just stick a thin 360 rad over the 200mm fans, but then I might as well just make the top radiator thicker, it's effectively the same thing, which is exactly what I'm going to do. Instead of the old 38mm rad on top, I'm ordering a 45mm rad. Now there's technically no room but I found the radiator rack can be raised and not interfere with the outer cosmetic shell. So I'm going to just use some MB standoffs to raise the radiator further up so it can be thicker. The bottom panel above the fans will now be filled with the flat radiator I really really love, and hopefully it'll cover up the ugly I/O and fan headers at the bottom of the MB.
     
    =======================
     
    There's an additional complication with the 2nd problem with conventional fan placement I mentioned towards the beginning. That is, paradoxically, stronger cooling is less efficient.
    What do I mean by this? Well think of a given CPU cooler and air flowing past it, if the flow is constant, the amount of thermal transfer happening here is NOT constant, it depends on the temperature difference between the air and the cooling fins. This means the hotter the fins, the more cooling you can do, and this usually means higher CPU temperatures. Therefore, in reverse, if you have a big 360mm rad on your 65w CPU, and it's 55 degrees under load, all that means is you are pushing a lot more air to cool 65w, than if the radiator was 120mm and the CPU is say, 75 degrees under load. Basically, you need exponentially more airflow (and therefore noise) to cool the same thermal power, if you want to keep your heatsinks cool.
     
    There is a way around this, and that's to reduce the temperature delta between the cooling fins and the thing you're trying to cool, it works because you aren't changing the temperature of your cooling fins, so you maintain the same amount of heat transfer between the fins and air, but you still make what you're trying to cool, cooler.
     
    So for the efficiency minded builder, you need to keep your priorities straight:
     
    1. Do not try to achieve unnecessarily low temperatures, cooling fetish is a real thing but you gotta remember the reduction in performance is exponential as your heat sink gets cooler. Just what kind of temperatures are good well that's a whole new can of worms we won't get into here.
    2. First thing you do to improve cooling is to improve the thermal interface, better paste, liquid metal, delid, lapping etc... Because these methods of reducing temperature are "free" and don't require more air flow / noise. This is one of the reasons why water cooling is so ridiculously good, you can minimize the temperature delta between lots and lots of cooling fins, and your CPU. Where as an air cooler's fins get colder very quick as they get more distant from the CPU.
    3. Increasing surface area of cooling fins. Air is just the worst at conducting heat, so a few millimetres between two cooling fins usually means there's like 1 millimetre of air in the middle that's not getting any heat transfer. So even with the same amount of flow, there's usually ways to dump more heat into it before the air leaves. This could mean denser fins, thicker rads, bigger rads, those all have their own pros and cons obviously, but find ways to dump more heat into the same amount of air. Average temperature of all the exhaust gas should ideally be as high as possible, that's a sign of an efficient cooling system.
    4. Increasing airflow should always be the last resort. Higher fan speed is less efficient, more flow separation, more vibration, more noise, but not as much more airflow. More speed also means the air has less time to contact the fins, less heat transfer per unit volume of air. The ideal situation you want to have is a big radiator at high temperatures, and a uniform, slow airflow through it. Not a jet engine with a small heat sink inside.
     
  17. Agree
    Chen G got a reaction from Bombastinator in Ryzen 3700x - High Temp Spikes On Custom Loop   
    First of all, 63 is not high at all so there's nothing to worry about.
     
    This is a heat transfer problem (or non-problem), doesn't matter how cold your water is, the thermal transfer between the silicon and the water is limited to a certain number of watts per degree temperature difference, depending on the specifics.
  18. Informative
    Chen G got a reaction from MarvinKMooney in Dare I say it, but I think you're all using fans wrong.   
    People talk about airflow management but I think everyone has been doing this wrong all this time. Conventional wisdoms like mounting fans on radiators, or having exhaust fans etc, it's just wrong and I have a build to prove it:
    Repeating the video description here, the fan speed on this build is controlled by the front panel speed for the demonstration, and it is on MAX SPEED. This is as noisy as it will ever get.
    I'm also not sticking some super lower power stuff in there, what you're looking at is a 7980XE and a 2080TI. Admittedly I am not overclocking the crap out of them but they are running above stock.
    So what about the thermals, am I just constantly butting up against 99 degrees and throttling? Absolutely not, a general figure I can give is 70 degrees maximum for GPU at 500w CPU+GPU power draw at 23 degrees room temperature. CPU thermals will depend on the interface, delid, lapping, LM etc, because that's going to be the biggest bottleneck.
    I'm sure this level of silence and thermal performance can also be done on a huge elaborate loop maybe with dual 480 rads or something. While a loop is required, I am using a pretty basic EKWB kit.
     

     
    To explain what I did here, I'm going to point out the top three problems conventional fan placements have:
     
    1. Wasted airflow. If you get air into your case and it just flows directly back out without cooling anything, you're generating noise for no thermal gains.
    This is extremely common with the standard front intake top exhaust case layout. Think about that top corner, what's going on there? The front fan sucks in air and it immediately goes back out the top, you've basically generated some noise for nothing. 
     
    2. Sub-optimal temperature difference. When air flows past a fin, the amount of heat transfer is determined by the difference in temperature, if you put a radiator at your intake, the air you take in have reduced cooling effect on everything else in the case, this again make you generate more noise with no thermal gains.

    Look at this here, we've got these radiators on the intake, which means your hybrid cooling cards are no longer hybrid they're basically just running on one 120mm rad, because the hot air isn't going to cool the rest of the air cooling heat sinks all that much.
     
    And then look at that traditional read exhaust fan, what's the point of that? Aren't you just sucking cold air out? Wouldn't it be better if all your available air either go through the top radiator or the graphics cards?
     
    3. Aerodynamic disruption. Placing fans right up against something, whether it's a solid piece of glass or a semi-permeable structure like a radiator makes it far less efficient, even for the best fans.
    To see how much of a difference this makes all you have to do is take off one of your fans, turn on the computer, and hold the fan either in open air, or up against its regular position. If you're running any significant fan speeds, the difference will be very noticeable. You're making a lot more noise, but defiantly less air. All those impressive fan specs you see on Noctua's website, well most of those are for open air operation, not up against a radiator.
     
    I basically designed a build specifically to eliminate all of these problems, and there is exactly one case not just compatible, but perfect for what I'm trying to do here:
     
    The Cooler Master SL600M
     
    Now if you read the reviews, you'll notice that it doesn't have the best reviews, a common complaint is high CPU temperatures, which is to be expected, as the graphics card is not only blocking the air path to the CPU, but also pre-heating the air, exacerbating the 2nd problem I mentioned above. However, the solution to that, is just forget about how the air interacts with the parts inside, but focus on the entrance and exit, because those are the spots where we can be certain all the air will have to go through.

    There's two giant 200mm intake fans, so we know air must come in here, and then since the front panel is closed, and there's no exhaust fan on the usual spot, we know the air must exist through the top side, where a radiator mount is conveniently located. At first I still had the traditional mindset of sticking fans on radiators so I had the fans over the radiator to suck out the heat, it worked but noise did not reduce compared to my previous build with the same 360rad and fans.
     
    But then it dawned on me, that there's just no reason to have those fans, if I just seal the case such that all air must escape through the radiator, then I will get an airflow through the radiator because the bottom fans are constantly taking in air, there's no where else for the air to go!

     
    There is actually no attempt from CM to seal the case for this use case, there's a huge gaping hole around the power switch which I had to cover up with cardboard. If I didn't do this none of this would work because the air would just go through those holes rather than through the radiator which has more resistance. There's also the issue of expansion card brackets. Most cards for cooling reasons will put exhaust grids on their brackets, but we can't have that in this build because the air will just escape through those grids rather than through the top radiator.
     
    Now let's look back at our three airflow problems and see how they've been solved:
     
    1. There is no wasted airflow at all, because all air must escape through the top radiator, which cools the CPU and GPU, so we do not generate any unnecessary noise.
    2. The air that gets to the top radiator will barely be carrying any heat because well, the CPU and GPU's heat are in the radiator, so we get maximum heat transfer.
    3. While there is an air filter against the bottom fans, there's basically zero obstruction near the fans, so they can operate very close to their open air performance.
     
    In fact, by doing this with this specific case we get some more additional benefits:
    4. Because the intake fan is 200mm, and max fan speed is only 800RPM, the noise to airflow ratio is extremely high and unmatched by any 120mm or 140mm fan.
    6. Because of the huge intake area of 2x200mm fans, intake airspeed is very low. Not only does this mean low noise, it also sucks in less dust/particles. the filter doesn't need to be cleaned for at least half a year or more.
    7. There's only two fans in the system (the one 120mm you see behind the panel is for back-up when the side panel is open), and it is extremely easy to set up an almost ideal fan curve to further minimize dust build-up (because noise is already minimal). I just stick a thermal probe in the radiator (or if you want to be fancy, a water temperature probe), and all you need to do is change the fan speed with the water temperature. You get an extremely gradual ramp, and you get exactly what your system needs for keeping cool.

     
    Again, this is at max fan speeds, and I'm placing the phone right against the exhaust port. You can see on the graph the noise peak is at ~150hz, a very subtle low frequency humm, if you have good enough ears to even hear it.
     

     
    The main reason most DIY cases don't do this is probably the requirement on sealing. The approach is actually not uncommon with purpose designed machines like this Mac Pro. While it doesn't have a water loop, there's similarly no fan on the CPU or GPU heat sinks. Instead the fans are at the front, which gets tunnelled to the heatsinks. This way you don't reduce the efficiency of your fans.
    Other examples of this are the trash can Mac Pro, and the new Xbox Series X, the ideas are the same. You somehow make a tunnel with all your heatsinks inside, and all you have to do is put one fan at the start or end of the tunnel to cool everything in the tunnel. No wasted airflow, and your heatsinks always get the coldest air possible. Could even take some slight advantage of the chimney effect.
     

     
    This is an experimental build I just made, while the thermal and acoustic performance of this is nowhere near as good as the big build. To my defence, there is only room for a 120mm rad and this machine, and despite being ITX, I think is as good as any full sized build with 120mm AIO. The airflow is less clean on this, but there's still no fan on the AIO radiator, the air pressure will find its way out of the system so it doesn't need to be linear.

    So Again I've completely sealed the case with packing tape, except for the 120mm AIO radiator, and the exhaust port of the blower 5700xt. Yes the blower 5700XT, and I actually specifically picked the blower because the regular third party rack cooler design would just allow air to escape through the rear bracket without passing through much of the GPU's heatsink. The 2 140mm RGB fans are both intake, and once the air gets in, they can only escape either through the GPU blower, or the CPU radiator.
     
    This is ITX and I'm working with only 2 140mm fans but thermals/noise efficiency is actually better than open air. And the reason is quite simple, I am effectively using 2x 140mm fans to push one blower 5700xt and one 120mm radiator. If it was just open air, I'd only have 1x 120mm and 1x ~50mm fan to do the same thing. So another way to think about this approach, is it allows you to mount more or bigger fans on your radiator than you other wise could, and run those fans at increased efficiency.
     
    The interesting thing is I got this case second hand, and the original owner gave me a mesh side panel and told me to use that to improve thermals. The fact that Phanteks sells that just means most builds in this case have worse thermals than open air. Also just from watching Gamer's Nexus, I get the impression that the accepted norm is that almost any case is not as good as open air. However by actually using fans correctly here, I have somehow achieved better than open air performance in an ITX case. Of course it won't beat a proper third-party rack cooler plus bigger AIO on open air, but that's not the point.
     
    I'm not trying to pick on anybody here, it's a sick build I love it but I'm just taking a random example to illustrate the problem.
    So he's got a radiator on the intake, which seems to be quite common now days. Provided the CPU isn't that hot so the pre-warming effect won't be too significant, the GPU is air cooled so it still has to work extra hard than if the radiator was at the exhaust. Just this one placement difference reduces the thermal/noise efficiency of your GPU.  There's three exhaust fans up top but they're too far away to be sucking the GPU's exhaust out so I'd guess they're sucking out a lot of the air from the radiator, but since your CPU is so efficient, you're moving a lot of air to cool a not very hot CPU, wasting existing airflow capability.
    Another stunning build, but this dual rad on both intake/exhaust layout is also pretty common and it doesn't maximize thermal/noise efficiency. The first obvious problem is fans against the radiator, so i already talked about that. But then if we think about this, you are basically taking the exhaust air of the first rad into the case, which is bad for the passively cooled components, and then you run that through the second rad, which will be no where near as efficient as the first one, but it costs just as much and generates just as much noise? 
    I'm not sure how much I can do better with a traditional case like this, because this is definitely partially the case's fault, there's really no room to mount unobstructed fans other than the traditional exhaust spot, which is not only unnecessary but counter productive since again, you'd rather have more air go through your radiators than through nothing. I guess what I would do here is just have one radiator as before, remove the fans, and put all other fans on intake, but then there's no dust filter on some of these so that's gonna be much harder to maintain.
     
    This looks psychedelic and interesting, but there's just massive inefficiency going on here, a lot of air will escape before they even get a chance to touch anything, especially through that top hole, And even if that was filled with a 360 rad instead it's not much help because the air through that fan will have generated the noise of 2 120mm fans, but without cooling much of anything except 1/3 of your CPU.
     
    Looking at all these builds here, I realize mine is seriously lacking in aesthetics, and that's going to be the focus point of mk.2 I am currently planning. No more cheap EK kits and industrial black tubes, this time I'll be using full EK Quantum line of parts. However I am in a big bind here, there's no way I'm going to buy another 2080ti at this point, so most likely the build won't be finished until next-gen GPUs come out, until then I'll probably just run some generic card with stock cooler, it won't look very impressive. I also haven't decided on if I wanna do hard tube, while that looks good it'll be such a pain to change anything, like for example upgrade the CPU.
     
    In terms of cooling, it'll mostly be the same as before, single 360mm rad. While there is space on the bottom intake for radiators, like some builds have done, I don't think I'll actually do that because I think that will give me overall worse thermal/noise ratio because I won't be able to use the 200mm fans. Unless I just stick a thin 360 rad over the 200mm fans, but then I might as well just make the top radiator thicker, it's effectively the same thing, which is exactly what I'm going to do. Instead of the old 38mm rad on top, I'm ordering a 45mm rad. Now there's technically no room but I found the radiator rack can be raised and not interfere with the outer cosmetic shell. So I'm going to just use some MB standoffs to raise the radiator further up so it can be thicker. The bottom panel above the fans will now be filled with the flat radiator I really really love, and hopefully it'll cover up the ugly I/O and fan headers at the bottom of the MB.
     
    =======================
     
    There's an additional complication with the 2nd problem with conventional fan placement I mentioned towards the beginning. That is, paradoxically, stronger cooling is less efficient.
    What do I mean by this? Well think of a given CPU cooler and air flowing past it, if the flow is constant, the amount of thermal transfer happening here is NOT constant, it depends on the temperature difference between the air and the cooling fins. This means the hotter the fins, the more cooling you can do, and this usually means higher CPU temperatures. Therefore, in reverse, if you have a big 360mm rad on your 65w CPU, and it's 55 degrees under load, all that means is you are pushing a lot more air to cool 65w, than if the radiator was 120mm and the CPU is say, 75 degrees under load. Basically, you need exponentially more airflow (and therefore noise) to cool the same thermal power, if you want to keep your heatsinks cool.
     
    There is a way around this, and that's to reduce the temperature delta between the cooling fins and the thing you're trying to cool, it works because you aren't changing the temperature of your cooling fins, so you maintain the same amount of heat transfer between the fins and air, but you still make what you're trying to cool, cooler.
     
    So for the efficiency minded builder, you need to keep your priorities straight:
     
    1. Do not try to achieve unnecessarily low temperatures, cooling fetish is a real thing but you gotta remember the reduction in performance is exponential as your heat sink gets cooler. Just what kind of temperatures are good well that's a whole new can of worms we won't get into here.
    2. First thing you do to improve cooling is to improve the thermal interface, better paste, liquid metal, delid, lapping etc... Because these methods of reducing temperature are "free" and don't require more air flow / noise. This is one of the reasons why water cooling is so ridiculously good, you can minimize the temperature delta between lots and lots of cooling fins, and your CPU. Where as an air cooler's fins get colder very quick as they get more distant from the CPU.
    3. Increasing surface area of cooling fins. Air is just the worst at conducting heat, so a few millimetres between two cooling fins usually means there's like 1 millimetre of air in the middle that's not getting any heat transfer. So even with the same amount of flow, there's usually ways to dump more heat into it before the air leaves. This could mean denser fins, thicker rads, bigger rads, those all have their own pros and cons obviously, but find ways to dump more heat into the same amount of air. Average temperature of all the exhaust gas should ideally be as high as possible, that's a sign of an efficient cooling system.
    4. Increasing airflow should always be the last resort. Higher fan speed is less efficient, more flow separation, more vibration, more noise, but not as much more airflow. More speed also means the air has less time to contact the fins, less heat transfer per unit volume of air. The ideal situation you want to have is a big radiator at high temperatures, and a uniform, slow airflow through it. Not a jet engine with a small heat sink inside.
     
  19. Like
    Chen G got a reaction from BiG StroOnZ in Dare I say it, but I think you're all using fans wrong.   
    People talk about airflow management but I think everyone has been doing this wrong all this time. Conventional wisdoms like mounting fans on radiators, or having exhaust fans etc, it's just wrong and I have a build to prove it:
    Repeating the video description here, the fan speed on this build is controlled by the front panel speed for the demonstration, and it is on MAX SPEED. This is as noisy as it will ever get.
    I'm also not sticking some super lower power stuff in there, what you're looking at is a 7980XE and a 2080TI. Admittedly I am not overclocking the crap out of them but they are running above stock.
    So what about the thermals, am I just constantly butting up against 99 degrees and throttling? Absolutely not, a general figure I can give is 70 degrees maximum for GPU at 500w CPU+GPU power draw at 23 degrees room temperature. CPU thermals will depend on the interface, delid, lapping, LM etc, because that's going to be the biggest bottleneck.
    I'm sure this level of silence and thermal performance can also be done on a huge elaborate loop maybe with dual 480 rads or something. While a loop is required, I am using a pretty basic EKWB kit.
     

     
    To explain what I did here, I'm going to point out the top three problems conventional fan placements have:
     
    1. Wasted airflow. If you get air into your case and it just flows directly back out without cooling anything, you're generating noise for no thermal gains.
    This is extremely common with the standard front intake top exhaust case layout. Think about that top corner, what's going on there? The front fan sucks in air and it immediately goes back out the top, you've basically generated some noise for nothing. 
     
    2. Sub-optimal temperature difference. When air flows past a fin, the amount of heat transfer is determined by the difference in temperature, if you put a radiator at your intake, the air you take in have reduced cooling effect on everything else in the case, this again make you generate more noise with no thermal gains.

    Look at this here, we've got these radiators on the intake, which means your hybrid cooling cards are no longer hybrid they're basically just running on one 120mm rad, because the hot air isn't going to cool the rest of the air cooling heat sinks all that much.
     
    And then look at that traditional read exhaust fan, what's the point of that? Aren't you just sucking cold air out? Wouldn't it be better if all your available air either go through the top radiator or the graphics cards?
     
    3. Aerodynamic disruption. Placing fans right up against something, whether it's a solid piece of glass or a semi-permeable structure like a radiator makes it far less efficient, even for the best fans.
    To see how much of a difference this makes all you have to do is take off one of your fans, turn on the computer, and hold the fan either in open air, or up against its regular position. If you're running any significant fan speeds, the difference will be very noticeable. You're making a lot more noise, but defiantly less air. All those impressive fan specs you see on Noctua's website, well most of those are for open air operation, not up against a radiator.
     
    I basically designed a build specifically to eliminate all of these problems, and there is exactly one case not just compatible, but perfect for what I'm trying to do here:
     
    The Cooler Master SL600M
     
    Now if you read the reviews, you'll notice that it doesn't have the best reviews, a common complaint is high CPU temperatures, which is to be expected, as the graphics card is not only blocking the air path to the CPU, but also pre-heating the air, exacerbating the 2nd problem I mentioned above. However, the solution to that, is just forget about how the air interacts with the parts inside, but focus on the entrance and exit, because those are the spots where we can be certain all the air will have to go through.

    There's two giant 200mm intake fans, so we know air must come in here, and then since the front panel is closed, and there's no exhaust fan on the usual spot, we know the air must exist through the top side, where a radiator mount is conveniently located. At first I still had the traditional mindset of sticking fans on radiators so I had the fans over the radiator to suck out the heat, it worked but noise did not reduce compared to my previous build with the same 360rad and fans.
     
    But then it dawned on me, that there's just no reason to have those fans, if I just seal the case such that all air must escape through the radiator, then I will get an airflow through the radiator because the bottom fans are constantly taking in air, there's no where else for the air to go!

     
    There is actually no attempt from CM to seal the case for this use case, there's a huge gaping hole around the power switch which I had to cover up with cardboard. If I didn't do this none of this would work because the air would just go through those holes rather than through the radiator which has more resistance. There's also the issue of expansion card brackets. Most cards for cooling reasons will put exhaust grids on their brackets, but we can't have that in this build because the air will just escape through those grids rather than through the top radiator.
     
    Now let's look back at our three airflow problems and see how they've been solved:
     
    1. There is no wasted airflow at all, because all air must escape through the top radiator, which cools the CPU and GPU, so we do not generate any unnecessary noise.
    2. The air that gets to the top radiator will barely be carrying any heat because well, the CPU and GPU's heat are in the radiator, so we get maximum heat transfer.
    3. While there is an air filter against the bottom fans, there's basically zero obstruction near the fans, so they can operate very close to their open air performance.
     
    In fact, by doing this with this specific case we get some more additional benefits:
    4. Because the intake fan is 200mm, and max fan speed is only 800RPM, the noise to airflow ratio is extremely high and unmatched by any 120mm or 140mm fan.
    6. Because of the huge intake area of 2x200mm fans, intake airspeed is very low. Not only does this mean low noise, it also sucks in less dust/particles. the filter doesn't need to be cleaned for at least half a year or more.
    7. There's only two fans in the system (the one 120mm you see behind the panel is for back-up when the side panel is open), and it is extremely easy to set up an almost ideal fan curve to further minimize dust build-up (because noise is already minimal). I just stick a thermal probe in the radiator (or if you want to be fancy, a water temperature probe), and all you need to do is change the fan speed with the water temperature. You get an extremely gradual ramp, and you get exactly what your system needs for keeping cool.

     
    Again, this is at max fan speeds, and I'm placing the phone right against the exhaust port. You can see on the graph the noise peak is at ~150hz, a very subtle low frequency humm, if you have good enough ears to even hear it.
     

     
    The main reason most DIY cases don't do this is probably the requirement on sealing. The approach is actually not uncommon with purpose designed machines like this Mac Pro. While it doesn't have a water loop, there's similarly no fan on the CPU or GPU heat sinks. Instead the fans are at the front, which gets tunnelled to the heatsinks. This way you don't reduce the efficiency of your fans.
    Other examples of this are the trash can Mac Pro, and the new Xbox Series X, the ideas are the same. You somehow make a tunnel with all your heatsinks inside, and all you have to do is put one fan at the start or end of the tunnel to cool everything in the tunnel. No wasted airflow, and your heatsinks always get the coldest air possible. Could even take some slight advantage of the chimney effect.
     

     
    This is an experimental build I just made, while the thermal and acoustic performance of this is nowhere near as good as the big build. To my defence, there is only room for a 120mm rad and this machine, and despite being ITX, I think is as good as any full sized build with 120mm AIO. The airflow is less clean on this, but there's still no fan on the AIO radiator, the air pressure will find its way out of the system so it doesn't need to be linear.

    So Again I've completely sealed the case with packing tape, except for the 120mm AIO radiator, and the exhaust port of the blower 5700xt. Yes the blower 5700XT, and I actually specifically picked the blower because the regular third party rack cooler design would just allow air to escape through the rear bracket without passing through much of the GPU's heatsink. The 2 140mm RGB fans are both intake, and once the air gets in, they can only escape either through the GPU blower, or the CPU radiator.
     
    This is ITX and I'm working with only 2 140mm fans but thermals/noise efficiency is actually better than open air. And the reason is quite simple, I am effectively using 2x 140mm fans to push one blower 5700xt and one 120mm radiator. If it was just open air, I'd only have 1x 120mm and 1x ~50mm fan to do the same thing. So another way to think about this approach, is it allows you to mount more or bigger fans on your radiator than you other wise could, and run those fans at increased efficiency.
     
    The interesting thing is I got this case second hand, and the original owner gave me a mesh side panel and told me to use that to improve thermals. The fact that Phanteks sells that just means most builds in this case have worse thermals than open air. Also just from watching Gamer's Nexus, I get the impression that the accepted norm is that almost any case is not as good as open air. However by actually using fans correctly here, I have somehow achieved better than open air performance in an ITX case. Of course it won't beat a proper third-party rack cooler plus bigger AIO on open air, but that's not the point.
     
    I'm not trying to pick on anybody here, it's a sick build I love it but I'm just taking a random example to illustrate the problem.
    So he's got a radiator on the intake, which seems to be quite common now days. Provided the CPU isn't that hot so the pre-warming effect won't be too significant, the GPU is air cooled so it still has to work extra hard than if the radiator was at the exhaust. Just this one placement difference reduces the thermal/noise efficiency of your GPU.  There's three exhaust fans up top but they're too far away to be sucking the GPU's exhaust out so I'd guess they're sucking out a lot of the air from the radiator, but since your CPU is so efficient, you're moving a lot of air to cool a not very hot CPU, wasting existing airflow capability.
    Another stunning build, but this dual rad on both intake/exhaust layout is also pretty common and it doesn't maximize thermal/noise efficiency. The first obvious problem is fans against the radiator, so i already talked about that. But then if we think about this, you are basically taking the exhaust air of the first rad into the case, which is bad for the passively cooled components, and then you run that through the second rad, which will be no where near as efficient as the first one, but it costs just as much and generates just as much noise? 
    I'm not sure how much I can do better with a traditional case like this, because this is definitely partially the case's fault, there's really no room to mount unobstructed fans other than the traditional exhaust spot, which is not only unnecessary but counter productive since again, you'd rather have more air go through your radiators than through nothing. I guess what I would do here is just have one radiator as before, remove the fans, and put all other fans on intake, but then there's no dust filter on some of these so that's gonna be much harder to maintain.
     
    This looks psychedelic and interesting, but there's just massive inefficiency going on here, a lot of air will escape before they even get a chance to touch anything, especially through that top hole, And even if that was filled with a 360 rad instead it's not much help because the air through that fan will have generated the noise of 2 120mm fans, but without cooling much of anything except 1/3 of your CPU.
     
    Looking at all these builds here, I realize mine is seriously lacking in aesthetics, and that's going to be the focus point of mk.2 I am currently planning. No more cheap EK kits and industrial black tubes, this time I'll be using full EK Quantum line of parts. However I am in a big bind here, there's no way I'm going to buy another 2080ti at this point, so most likely the build won't be finished until next-gen GPUs come out, until then I'll probably just run some generic card with stock cooler, it won't look very impressive. I also haven't decided on if I wanna do hard tube, while that looks good it'll be such a pain to change anything, like for example upgrade the CPU.
     
    In terms of cooling, it'll mostly be the same as before, single 360mm rad. While there is space on the bottom intake for radiators, like some builds have done, I don't think I'll actually do that because I think that will give me overall worse thermal/noise ratio because I won't be able to use the 200mm fans. Unless I just stick a thin 360 rad over the 200mm fans, but then I might as well just make the top radiator thicker, it's effectively the same thing, which is exactly what I'm going to do. Instead of the old 38mm rad on top, I'm ordering a 45mm rad. Now there's technically no room but I found the radiator rack can be raised and not interfere with the outer cosmetic shell. So I'm going to just use some MB standoffs to raise the radiator further up so it can be thicker. The bottom panel above the fans will now be filled with the flat radiator I really really love, and hopefully it'll cover up the ugly I/O and fan headers at the bottom of the MB.
     
    =======================
     
    There's an additional complication with the 2nd problem with conventional fan placement I mentioned towards the beginning. That is, paradoxically, stronger cooling is less efficient.
    What do I mean by this? Well think of a given CPU cooler and air flowing past it, if the flow is constant, the amount of thermal transfer happening here is NOT constant, it depends on the temperature difference between the air and the cooling fins. This means the hotter the fins, the more cooling you can do, and this usually means higher CPU temperatures. Therefore, in reverse, if you have a big 360mm rad on your 65w CPU, and it's 55 degrees under load, all that means is you are pushing a lot more air to cool 65w, than if the radiator was 120mm and the CPU is say, 75 degrees under load. Basically, you need exponentially more airflow (and therefore noise) to cool the same thermal power, if you want to keep your heatsinks cool.
     
    There is a way around this, and that's to reduce the temperature delta between the cooling fins and the thing you're trying to cool, it works because you aren't changing the temperature of your cooling fins, so you maintain the same amount of heat transfer between the fins and air, but you still make what you're trying to cool, cooler.
     
    So for the efficiency minded builder, you need to keep your priorities straight:
     
    1. Do not try to achieve unnecessarily low temperatures, cooling fetish is a real thing but you gotta remember the reduction in performance is exponential as your heat sink gets cooler. Just what kind of temperatures are good well that's a whole new can of worms we won't get into here.
    2. First thing you do to improve cooling is to improve the thermal interface, better paste, liquid metal, delid, lapping etc... Because these methods of reducing temperature are "free" and don't require more air flow / noise. This is one of the reasons why water cooling is so ridiculously good, you can minimize the temperature delta between lots and lots of cooling fins, and your CPU. Where as an air cooler's fins get colder very quick as they get more distant from the CPU.
    3. Increasing surface area of cooling fins. Air is just the worst at conducting heat, so a few millimetres between two cooling fins usually means there's like 1 millimetre of air in the middle that's not getting any heat transfer. So even with the same amount of flow, there's usually ways to dump more heat into it before the air leaves. This could mean denser fins, thicker rads, bigger rads, those all have their own pros and cons obviously, but find ways to dump more heat into the same amount of air. Average temperature of all the exhaust gas should ideally be as high as possible, that's a sign of an efficient cooling system.
    4. Increasing airflow should always be the last resort. Higher fan speed is less efficient, more flow separation, more vibration, more noise, but not as much more airflow. More speed also means the air has less time to contact the fins, less heat transfer per unit volume of air. The ideal situation you want to have is a big radiator at high temperatures, and a uniform, slow airflow through it. Not a jet engine with a small heat sink inside.
     
  20. Informative
    Chen G got a reaction from Earthworm Jim in NON-GAMING BUILD (Scientific) - Building a computer for running molecular dynamics codes (and maybe some computational fluid dynamics).   
    No idea if what you're doing can be GPU accelerated, but if it can, you could potentially be missing out several folds of performance. No, you do not want to cheap out on PSU for something that will be running full power for extended periods of time. A properly designed airflow should be sufficient with just air coolers. Liquid cooling solutions are not economical in terms of performance per dollar. Not sure, I've heard about some issues with Ryzen and Linux.
  21. Agree
    Chen G got a reaction from Castdeath97 in (Update: announcement imminent) A new generation of thermal throttle - new intel laptop chip found   
    Because it doesn't matter if it was.
    You knew what the base clock is, they tell you right on the product descriptions, that's what you're buying, and there's no reason to complain when it clearly does reach that base clock. And there is certainly no reason to say it's "throttling" when it clearly isn't.
  22. Agree
    Chen G got a reaction from jones177 in How to choose a new monitor?It's a right time to upgrade?   
    The perfect monitor now days is an OLED TV.
  23. Like
    Chen G got a reaction from Bombastinator in Need Help with choosing CPU air cooler   
    Why are you not happy? What's wrong with these temps?
  24. Funny
    Chen G got a reaction from IsaacG in Modern and retro Gaming on a CRT in 2020   
    CRT basically has all the advantages of OLED, plus the advantage of not having square pixels.
    I did use CRT long into the LCD era but I stopped once I got some decent IPS LCDs.
    And today I just use OLED. If I want the CRT style effect I just take off my glasses and turn on BFI.
  25. Informative
    Chen G got a reaction from Ayush007 in Best 4k monitor under Good budget for gaming   
    Get an LG C9 OLED TV
    real HDR on OLED is so much better than any of those LCD gaming monitors.
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