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Hey, so I'm building a loop for my brother's PC. We're using an NZXT H200i, so to save space on the pump, we bought this combo https://www.aliexpress.com/item/10000411453657.html after Optimum Techs good review of it. However, the pump acts weirdly, for example, it just wont pump water most of the time. The motor is spinning, but it just doesn't push water. Then other times, it pumps but at a very slow flow. I say 10% of the time we could get it to spin normally. When it was in the system, tilting it to the front and power cycling a dozen times we got it to spin quickly as it should. When it spins quickly, the speed control and everything works. But after draining the loop, looking at the pump, and seeing nothing physically wrong, we can not get it to spin at the proper speed outside the case. I recorded a video of it spinning slowly, hence having bad flow and being quiet, and while the system was tilted and it going "fast". Sorry for the bad phone quality. Is this pump defective and we should return it? Thanks for the help. https://www.youtube.com/watch?v=gvFvfVuEYfc&ab_channel=Gecko.

I have Black magic sh**t going on, because there is no logical explanation for this. I have both Digital Flow meter with screen and Transparent square Water tank so i can confirm the flow meter results Visually. [and its not PWM, its disabled and hardware monitor in bios shows constant pump speed] 1st Loop Try: 18W LAING DDC Pump inside Bykski Reservoir combo > GPU Block > GTX360 Rad > Heatkiller IV CPU Block > GTS480 Rad > Back to res I had water filter + sliding valve that has small holes around the tube + 5 quick disconnects 0.6L/m 2nd Loop Try: Removed water filter and valve, NO CHANGE 3rd Loop Try: Added Barrow D5 pump Full speed 4800RPM after the LIANG DDC 4300RPM the flow starts strong and then drops back to 0.6 L/m Even with just the DCC by itself enabled, sometimes it would start at 2L/m and the flow is so fast the water looks like boiling, but then it slowly drops. I left to do car test for 1.5 hour, let the system bleed air with 2 pumps on FULL SPEED, came home to see 0.4L/m 4th Loop Try: I get psychotic and remove all QD No change, flow starts strong, sometimes as fast as 4.0L/m and then slowly drops down [again before anyone says the flow meter is broken, i confirm everything visually, when its strong it looks like boiling water and sounds like waterfall, when it goes down, it looks like dripping] MY GTS480 is installed with ports down, I assume maybe air pocket moves and block, i flip the HUGE Phantecks 719 case on its top, small change. 5th Loop Try: I decide to remove the GTS480 from the loop and see if it helps. Now I have DDC 18W full speed/Res combo > D5 Full speed > Heatkiller IV > GPU block > GTX360 > back to res Same thing, flow starts strong and then drops down, I would pull my hairs out if i had any Right now when i type this post, I booted the PC and the flow already dropped to 1.7L/ [102L per hour]and stays there, but its not enough for 2 pumps and thats with LAING 18W DDC running full speed and Barrow D5 running full speed, only GTX360 rad, CPU block and GPU block installed. Guys im loosing my mind here, what can it be? P.S.I plan to disassemble and re-do anyway, need to remove the wifi card from below the shroud, the damn thing has 128 byte payload and it affects all PCIe devices connected to the same switch But im afraid that when i re-assmeble ill return to same situation, I also plan to install the GTS480 with ports up, the GTX360 is at the top of the case so i cant change its position anyway.

Hi together, I'm interested in buying a DDC Pump, one with PWM control and want to ask if someone have some experience with these pumps. 1: Are they reliable? 2: Do they actually need active cooling under their pcb? 3: Do heavy brass tops really reduce vibrations (like the Alphacool Eisdecke, or the one from Phobya)? 4: Is the flow rate higher compared to a D5 at the same noise level? For the active cooling aspect, I thought of buying a chunk of copper, drill some holes in it with G 1/4 threads and connect the pump bottom case in my cooling loop.

Hey there, I am looking for a full metal DDC pump top. Which one would you recommend?

Hey all, Ive been a pc enthousiast for a while and i'm about to tackle my first custom waterloop in my "newly build" system. Recently ive upgraded my case to a ThermalTake View 71 and started collecting parts for my watercooling build. So far the parts i'm going for and/or already have are : - Asus ROG Crosshair VIII Formula ( it has ekwb block on it for the vram the cpu is still seperate ) - Asus GTX 1080ti ( wich already has a ekwb block on it and backplate ) - Corsair Vengeance RGB 32gb (4x8gb) 3200mhz - AMD 2700x ( currently possibly changing to a 3950x or a 5900x ) - Corsair m.2 970 pro 1tb x2 - Corsair ssd 2tb - Corsair hx1200 watt powersupply - Corsair Hydro X Series XH303i RGB custom watercooling kit ( for good reason explained below ) - Corsair Hydro X Series XR5 360mm radiators x2 ( 1 included in the kit and 1 bought seperate ) - Bykski Distroplate for the ThermalTake View 71 ( 360rad size ) - Phanteks D140 Distroplate ( small size replacing the rear exhaust fan ) - iFixit Pro Kit ( thanks LTT ) Now for cooling wise clearly i want to go custom loop since i already have acquired some or atleast most parts. I'm still awaiting the arrival of both distroplates and some minor stuff but ive already started to build most of what i have into the case. The issue that i am facing or atleast that i think i am facing is. The Bykski Distroplate has a mount on it for a pump and i'm quoting the manufacturer atm "compatible with various brands ddc pumps or bykski own". Corsair XH303i comes with a kind of reservoir wich has a ddc pump wich i have taken apart and normaly ( according to my calculations ) is gonna fit on the Bykski distroplate. Now all the components i have and want to watercool or better sayed have a loop on it are the cpu, vram, gpu, 2x 360rads, 1 big distroplate wich wil function as reservoir and pump, 1 small distroplate. The thing i'm worried about or am wondering is, is that ddc pump gonna manage it for that entire loop or will i need to add a second pump/reservoircombo to the loop? Thanks in advance for any help or advice on this matter. Greetings Chimmie ps : picture added is how the build currently looks ( i have a corsair h100i running on it atm and a gtx 1070 to test fit everything and ofc testing to see if everything works and what my layout is gonna be, preplanning tubes and bends and such ).

Currently gathering the parts to water cool my rig in my NZXT H710i case, and decided to use a distro plate to help keep the tubing runs simple and clean. Found a Barrow distro plate at TitanRig and decided to make that my first purchase. I'm planning on using the EKWB DDC 4.2 pump to drive the whole thing but I'm not sure how I would integrate the pump to the plate. I've included a couple videos detailing what I think I understand about this distro plate.

So I'm about to buy parts for a liquid loop in an itx case, and I planned on using this pump/res combo unit, https://www.amazon.com/XSPC-Ion-Reservoir-Pump-Combo/dp/B01BA3LY64 It says its a DDC pump, and after doing a little looking, apparently DDC pumps run louder and hotter. I really have no idea what I'm getting into, and I wanted to know if there was any advice I could get about how hot/loud it really is, should I look for a similarly small D5 pump, and considering there will be NO airflow to the pump, will it be fine in my case?

Need some input! Setting up a new custom loop with L360 kit from EKWB. Can't get the DDC pump to kick in? Here's is what i've tried: 1) Jumpered the PSU (confirmed working as PSU fan runs). Plugged SATA power with SATA power adapter to "Pump testing adapter" but NO GO. Also, can't get a case fun to run with this method. 2) I've tried that SATA 'adapter" with another PC and can't make a fan go either. >Unplugged optical drive SATA and plugged in adapter and fun. NO GO. 3) I created a long extension cord for a fan header on another PC. And while that spins a case fan just fine, it won't make the pump go. I've turned up that fan header to 100%, but NO GO. I'm worried that testing adapter is bad? And that I'm not getting enough voltage through the extension cords i've tried (makes fan go, but not pump) any ideas. I've submitted a ticket to EKWB, but hoping I can get a easy solution. The DDC pump in this kit ONLY has a 4 pin input.

Hi everyone, I'd nearly finished my custom watercooling loop when my pump started acting up. It's a Laing DDC with the bitspower 250 upgrade kit, bitspower top, and EK heatsink. I'm using monsoon compression fittings. When I start the pump, the water level in the reservoir briefly drops, then becomes constant. The pump starts making a sharp crackling sound. When I stop the pump, the water level returns to what it was. The video attached shows this in more detail. Does anyone have any suggestions? pump.mp4

Hi, I have an idea of how this will work but i wanted to run it by a few people who might have done something like this before. In short, I'm building a system using an ASUS Z270I (itx) motherboard, the board has the following available fan headers(and pin outputs): CPU Fan - PWM (ground, +12 V, rpm, PWM Signall) CHASSIS FAN - (ground, +12 V, rpm, +5V) AIO PUMP - (ground, +12 V, rpm, +5 V) I have two radiator fans (120 mm pwm), 3 chassis fans (2x80 mm, 1 x 140 mm) and the pump. My original plan was to run the 2 radiator fans off the cpu fan header, the pump off the AIO header (note it has a 12 V power feed direct from the PSU also) and the 3 remaining fans off the chassis fan header. However, i did not realise that the AIO header did not support PWM, thus, if i use this header for the pump i will only ever have a fixed pump speed 42% of maximum, that doesn't seem all idle but also not the end of the world? But... I also know that this board can likely control fans via dc voltage on the none PWM headers, so my thinking was what if i connected the pump PWM signal pin to the +12V pin instead perhaps I could have DC control of the pump speed via the AIO header instead? After all, PWM is just a digital way to mimic a voltage so i doubt the pumps going to notice the difference between a 7V PWM signal and a 7V DC signal? Here's the link to the pump i'm using https://www.ekwb.com/shop/ek-ddc-3-2-pwm-laing-ddc-3-2-pwm Thanks, Christian

Hey everyone, I have an EK DDC 3.2 PWM pump running my EK X360 cooling kit setup in my PC, heres the specs: Phanteks Enthoo Luxe (Tempered Glass) ASUS Z170 Pro Gaming Motherboard Intel I7-6700K (Running overclocked courtesy of SCAN) Corsair Vengeance 16GB DDR4 RAM Corsair Force 3 240GB SSD Seagate Barracuda 2000GB HDD Nvidia 980ti Zotac Amp! Extreme Graphics Card EVGA Power Supply (800W-ish as its covered by the shroud and I can't remember :S) EK X360 Watercooling Kit w/ Mayhems Pastel Red Coolant 2x Corsair AF140 3 pin fans I am aware its a bit overkill cooling for simply a CPU but its a work in progress and what can I say, I like 'em chunky. I am trying to control the pump and fans using the ASUS Dual Intelligent Processors interface via Fan Xpert 3 (all up to date as far as I am aware), the pump is on the CPU header and the 3x 4 pin EK Vardar fans are on the supplied EK splitter. I have noticed that my pump RPM will fluctuate around the chosen point if I leave it there which is an issue as I leave my pump on a static rpm at all times. The fluctuation will occur at any rpm, and I mean ANY rpm and fluctuate 1000-2000 in range. Does anyone here control their DDC pump via their mobo software and maybe come across this problem? Or does anyone have a more ideal solution for me? I am aware many folks prefer SpeedFan however I could never get it working right even when I had disabled the ASUS software control in the BIOS.

Hi, I've read some tips that was thankfully provided by this forum. I appreciate the community here helping newbies like me. So I've made some photos to see If I've understood the flow of the pump well. My main concern is how do I mount the D5 pump on the left side of the Xforma case when using 'theDDC/D5 Pump Mount Sled'. What I thinking is to use a D5 pump on the mount sled to make the loop flow cooling liquid as much as possible. However, my concern is what to use to push the liquid upward to reservoir and the hardware waterblocks. If there anybody to guide me, please lend me some knowledge. Thanks Kim

I recently finished my first waterloop and cleaned it completely with Mayhems blitz 1 and 2. Now after flushing it out and trying too boot the system the cpu reaches over 90 degrees after about 30 secs to a minute in bios. Does anyone know why that could be?

Anyone have experience with Barrow DDC Pumps? I have yet to find anyone talking about it, but they go for a fraction of EK's price (also factoring in where I live, EK's products becomes very unreasonably priced as I also have to pay USD$50-60 import tax per item). I have seen an Amazon review stating that it's not authentic Laing pumps as Barrow's only uses 18W instead of 23W. Is this true? Also, what are the internals made of? Will it conflict with my Copper/Nickel loop? Finally, how does it perform comparing to EK's? All I see in Amazon reviews are 2 extreme sides of the story: one side says they are top quality and runs very quietly, the other side says its literally shit??? Please help if you have experience with these pumps. Thx!

I used ScreenBright to controll the brightness of my previous monitor (XB240H, 1080p 144hz) but it isn't working with my new monitor (XN271HU, 165hz 1440p TN gsync). I didn't see an DDC/CI option in the settings of my new XN271HU like there was on my previous monitor, but in the user manual is says: I'm using the DP cable and tried it with and without the usb cable that came with the box. In screenbright I can currently change everything except brightness. Also when I change something, for example contrast. The contrast in the monitors OSD will remain the same. So it is changing the contrast but not working properly with the OSD. Sadly enough my brightness won't change. I dont know what is wrong. I contacted acer support and they didn't know anything, the only thing they said is that my new monitor works better with an acer predator desktop.

So I am thinking of watercooling an i7 6700k for my next build. I will be building inside the fractal design nano s and so space will be at a premium. I want to create an EK pump res combo, and their own solutions only have combined intake / outlet on the bottom, where as I want inlet from the top of the res. I can either get an EK topped d5, 6mm mm fitting and create a 6mm plastic insert to even out the pressure, or do the same with the elite DDC pump. Both should give me a vertical pump res combo (I will use an x3 150 lite res) but is a d5 or DDC better in this situation. Btw I know bitspower has a pump top and res upgrade kit but here in the U.K.,I can only seem to find the top, and not the upgrade kit, not too mention I think I need extra O rings and so there I am confused.

I plan to do a custom loop including both my CPU and my GPU, with 360mm of rad space, will one EK DDC pump be powerful enough or should I get two?

So when I start my watercool build how safe is it to plug the pump into the mobo because I cant find any adapters that ship to NZ. So I want to know if its safe to use that pump and any other ways I can use it without using the mobo can I plug it into the psu. But then I lose the PWM. Ill probably have it on hundred percent all the time because the loop could be around 5 metres long https://shop.ekwb.com/ek-xtop-ddc-3-2-pwm-elite-acetal-incl-pump

Just trying to decide on what pump (or pumps?) I want for an upcoming build. The build will be 1 CPU block (or mono block if it's available), 1 gpu block, two 280 rads, and either one 200 rad or one 180 rad (depends on what fits). This is the rough idea, as I don't have the case I'll be using just yet. Now I've read plenty on ddc vs d5 but I still can't decide. If I was going D5, it would be this. If I was going DDC, it would be this. The thing is, I could go dual DDC at that price and it would be near the same price of a single D5. Or I could just go with the single DDC, but since it's a reduced power model I don't know if it would be enough for the build. Yes, I know I would need a top if I went with the single DDC. There's the same model with a top for slightly more if I went single DDC. Thoughts?

So, my ordeal with my custom loop continues. The struggle is real. My ghetto P500 pump recently died, so I decided to stop being cheap and piece together my loop with parts that were made this decade rather than the ancient stuff I had previously been using. This meant a new reservoir not held together with shower caulk and a pump that, well, pumps. Being the bright spark that I am, I decided to get an MCP350 with the Bitspower DDC Top and the accompanying reservoir upgrade kit. However, now that I have the parts in my hands, I've come to the shocking realization that the combined pump/reservoir has one outflow on the base, and one inflow on the top of the reservoir. Is there some sort of gypsy magic I can invoke to somehow fill this loop through the singular inflow, or do I have to shell out for a different top for the reservoir?

What are the benefits of buying one rather then the other? As far as I an aware DDC pumps have a higher pumping pressure for vertical pumping, but run hotter and slightly louder; where as D5 pumps have a faster flow rate? Is this information accurate? Also DDC pumps and tops tend to be cheaper than D5 (at least here in the UK)

Announced at CES 2014, this pump was something I was looking forward to a lot- especially coming from the MCP35X I have been using so far. So when I started my big build and realized a single MCP35X wouldn't necessarily be able to handle what I planned for the loop I got in touch with Bryan and he helped me tremendously by sponsoring the build with 2 MCP50X pumps. This review is a result of that, mostly because I was curious to see how these handled in comparison with the other pumps I since procured- another MCP35X and a Laing D5 Vario. Unboxing The pumps come in a glossy black box, in contrast to the usual Laing simple white boxes. A sticker on the side gives the specs of the pump. If you notice, the pump has advertized head pressure higher than the MCP35X but at a lower max flow rate. But what's inside is what matters so let's take a look: Inside is the pump itself in a bubble wrap pouch for protection, 2 mounting screws, 2 neoprene mounting pads and an instruction manual. Let's take a look at the pump now: The first thing I noticed was how "solid" it is compared to the MCP35X- weighs more and feels sturdier as well. G 1/4" threads tapped in for inlet at the top and outlet coming off the horizontal side. The "Warranty void if removed" sticker. But, as we will see soon, this time the sticker is actually there for a reason- warranty will indeed be void if one opens up the pump for any reason unfortunately. SATA for power! If everyone replaced molex with SATA for power, the world would be a much better place Now I realize there likely won't be any 3rd party tops but never say never. The pump body sans top is pretty much 1" tall, and the entire unit is 2.4" x 2.4" x 1.8" for those looking for compact pumps. In fact one can see the pump is only just taller than the MCP35X unit (2.4" x 2.4" x 1.35"). But, if claims of this pump not needing a heatsink/fan are true, then things change drastically: This is even before the heatsink feet come in. The heatsink incidentally is 3.15" x 3.15" x 0.71" (Again before the feet) so the "compact" MCP35X isn't necessarily so. Speaking of a not compact pump, Now I did have a Bitspower delrin D5 mod top on but there was something wrong with that top resulting in big performance degrading. So for the tests coming up, I used the stock top as seen above. Disassembly I must note that the disassembly was done post testing to make sure there was no issues arising from possibly incorrect reassembly. First up, the warranty sticker and the 4 philips head screws in the bottom: Inside we see something vastly different from the Laing DDC: The magnetic impeller/rotor unit is a totally new part made by Swiftech for this. We see a gasket/O-ring that by touch and bounce characteristics suggests is made of Buna-N. I could be mistaken here but suffice to say that it does the job. Unlike the Laing DDC, there is no ceramic ball bearing here. I am not familiar enough with these parts to claim what this is, but the ball bearing was the one piece prone to wear and tear in the DDC pumps. Swiftech claims the same 50,000 hours of MTBF for both the MCP35X and MCP50X. Now let's remove the motor unit out: No, that's not water. It is in fact a glue of sorts holding the PCB and motor tight. I also opened up an MCP35X for a side by side comparison (MCP50X part on left, MCP35X part on right): Now here's why Swiftech has decided to enforce voiding warranty if the MCP50X is opened: These two small washers are part of the impeller unit and hold it in place on the pump motor. Here's a look at how the unit looks without the washers: and how it looks with them: Needless to say, if you aren't looking for these then it can be very easy to lose them. The thicker, outer washer also is shaped to fit in perfectly: So needless to say, it took careful and steady hands to put these back together. While I don't really see how the washers would come out when removing the pump top (assuming upright position), I can understand the reasoning behind the warranty being void. There are plans for another top from Swiftech but if that comes to fruition then it will likely only be sold pre-installed with the pump for this very reason. Performance testing Since I had 2 each of the MCP50X and MCP35X as well as an MCP35X2 top, I decided to go ahead and make 2 test loops- one close to what I will eventually have in my GPU loop and another more representative of a typical user's loop. The components are listed below: Reservoir: FrozenQ Liquid Fusion 400 mL cylindrical reservoir Controller/readout: Aquacomputer Aquaero 6 XT Pressure drop readout: Dwyer 490-1 wet-wet manometer (with Koolance NPT 1/8" male to G 1/4" female adapters) Flow meter: Aquacomputer High Flow non-USB previously calibrated from a King Instruments rotameter Sound meter: Extech AN10 sound probe previously calibrated in a sound lab Temperature: Rosewill IR thermometer High restriction loop (components between the high and low pressure ports on the manometer): Watercool Heatkiller Mo-Ra3 420 Pro 9x140, 4 Koolance QD3s, EK FC 780 GTX Classy water block and 2 Bitspower 1/2" x 3/4" compression fittings w/Primochill Advanced LRT Clear 1/2" x 3/4" tubing Low restriction loop (components between the manometer ports): EK Supremacy Evo CPU block, Swiftech R9-LE full cover water block, XSPC AX480 radiator with 6 Bitspower 1/2" x 3/4" compression fittings w/Primochill Advanced LRT Clear 1/2" x 3/4" tubing By "2x MCP50X" or "2x MCP35X", I am referring to connecting them together using fittings and not a dual top (as in the case of the MCP35X2). Each loop was set up inside an isolation box for a controlled ambient temperature (20 ºC +/- 0.25 C) and ambient noise level. Due to the box not being personal property, I wasn't able to decouple any pumps by using any double sided foam/neoprene so the sound levels measured may well be higher than what people will notice in general. Each pump was connected to the reservoir using an XSPC rotary male-male adapter except in the case of the D5 where more compression fittings/tubing had to be used with the stock barbs. Measurements were taken after the loop was bled of air and a further 5 hours had passed for steady state to be achieved. In the case of multiple pumps, average pump noise and temperature is an average of the two pumps together. Each measurement set was repeated 5 times for statistical accuracy. Finally, the MCP35X pumps were used with the heatsinks on because the isolation box did not have the best air flow and I didn't want to take the chance of getting them too hot. So temperatures there may well be better of worse compared to your situation depending on air flow, use of heatsink, fan etc. PWM Response Anyone familiar with the PWM controlled Laing DDC is aware of the short duty cycle- typically between 20-60% PWM signal. So the near linear response spanning the entire PWM range for the MCP50X was impressive to me. The same trend holds with multiple pumps: Part 1: High restriction loop The pressure drop from the components listed above reached a max of > 7 psi at the max flowrates achieved! Let's take a look at the flowrate behavior with PWM control, and also RPM: As was the case with the PWM response curve, flowrates can be controlled near linearly with the MCP50X which also has a larger range of flowrates provided- 1.3 GPM to 0.15 GPM. A similar scenario is seen when the multiple pumps are added in: Looking at this, one would be tempted to think the MCP35X is a better performer. But remembering how the PWM response is for the pumps, and plotting the flowrate vs RPM curve (Where the D5 vario comes in as well), things look different: Both the MCP50X pump samples (randomly picked, with distant serial numbers) performed near identical, which is good to see. The production of these pumps doesn't seem to have any effect of variability then. At the same pump RPM, the MCP50X puts out a higher average loop flowrate compared to the MCP35X and also the D5 (which to be fair isn't in it's strong zone here anyway). When adding in the multiple pumps, things don't change much: The one noteworthy point here is the effect of a dual top- especially one that is arguably the best performing top on the market. The MCP35X2 is a better raw performer here and I can only imagine what an MCP50X2 dual pump top would do here if Swiftech were to ever make one. But what about pump noise? The MCP50X at full speed is quite loud. There's no denying it here- both pump exhibit near identical sound profiles. But when toned down to 70% or below, they get a lot quieter- I can't emphasize enough how big of a change it is going from 100% to 70% to 50%. As seen above, they get into D5 noise territory which is remarkable. When looking at multiple pumps as well: It is a similar story, except with the MCP35X2 top again being exceptional. I was skeptical of how it was that much quieter than single pumps at the same flowrates so I set up the loop outside at home- no difference. Next up, pump temperatures (remember that the MCP35X pumps were with the passive heatsink on, and the D5 is cooled by the loop): The D5 was the coolest, and it makes sense too. Even without a heatsink on, the MCP50X pumps were cooler than the MCP35X w/HS so that's impressive again. I have heard of way too many dead DDCs because of overheating so this is a good piece of news. When adding in multiple pumps, the same story comes up- a good dual pump top is better than 2 pumps connected together: There is quite an appreciable increase in temperatures in the case of 2x MCP35X. I must note here that it was the 2nd pump (not directly connected to reservoir) that was the hotter of the two. Heatsink mounting was not a factor here either. Part 2: Low/medium restriction loop The maximum pressure drop measured was a little over 3 psi here. I only ran single pumps here- given the flowrates achieved with single pumps alone the need for dual pumps is more for redundancy here than performance in my opinion. Let's see how the flowrates change with PWM signal and then also RPM: The maximum flowrates achieved are quite higher here than in the previous loop which again agrees with what was expected. The D5 here performs much better than before also but the MCP50X and MCP35X continue to right up there at the top. Once more there is a larger range of control with the MCP50X vs MCP35X. When look at flowrate vs noise, a similar case as with the high restriction loop emerges. The MCP50X is still the loudest pump at full speed/near full speeds, quietens down a lot at 70% PWM signal or lower and is as loud (quiet) as a D5 afterwards. For people looking at 1 GPM flow or thereabouts (whether this number is anything more than a suggested rule of thumb or otherwise), the D5 is the quietest followed by MCP50X and then the MCP35X. When properly decoupled, I expect the trend to continue but at lower absolute numbers. There was no pump vibration in any case to add to noise. Here's one of the more telling graphs. At low/med restrictions and tuned down via PWM, the MCP35X pumps get hot really quick even with a passive heatsink on and a bit of airflow in the chamber. The D5 and MCP50X pumps in comparison run much cooler. Summary The MCP50X is available for sale in the USA at an msrp of $69.95 with reseller pricing going lower with discount codes if applicable. The MCP35X has an msrp of $99.95 but can be found for $85 or lower new. A stock D5 vario, such as the Swiftech MCP655, runs at an msrp of $108.95 but identical D5 vario pumps can be bought for $79 or lower. The MCP35X heatsink is a further $14.95 and a decent D5 top runs another $30+ on average. MCP50X definitely is the most bang of your buck pump here. In terms of size and connectivity, it is the most compact pump (excluding the MCP35X without HS) and has a SATA connector for power. On the flipside, it only comes with PWM regulation so and not all 4 pin "PWM" headers are actual PWM controllers as seen here: http://www.swiftech.com/pwmcontrollers.aspx When comparing MCP50X vs MCP35X (or any Laing DDC for that matter), if PWM control is not a hindrance then go with MCP50X. It is louder at full speed but gets quieter quickly, offers more head pressure, has a "fuller" PWM response curve and runs cooler. It is also a lot less expensive. There have been no long term tests on the pump yet, for obvious reasons of availability only being a couple of months now, but so far so good. When comparing MCP50X vs Laing D5 (unfortunately I do not have a PWM controlled D5 nor a D5 Strong), the former is a no brainer in a high restriction loop. But in a more typical low/med restriction loop, I would probably go with a D5 if space or cost is not a concern. If it is, then at ~1/2 the cost of a D5 with a 3rd party top the MCP50X is a good choice. Irrespective of what you go with, Swiftech has done a good job here. I would have liked to see possibly longer cables (sleeved cables are a nice bonus as well) and really would love to see more tops- a plexi version and also a dual pump top for those having a different aesthetics preference or wanting redundancy/more performance. The only reservoir that mates directly with the pump is Swiftech's own MCP35X-Res but a simple male-male adapter will connect just about any reservoir out there.