Radiator fans

[Belgar]

Hi,

 

I have NZXT kraken X72 with 3 default fans on it. They get pretty noisy even at Silent fan profiles. Would getting 6x NOCTUA NF-A12x25-PWM fix the issue? Will this be worthy investment that will improve a. performance and b. acoustics.

(btw I have NZXT 710i case and CPU is 3900X @4.45GHz)

Thanks a lot

[Hairless Monkey]

Basically yes. The NOCTUA fans are known to provide better air flow with less noise. I'm sure 6 of them running full speed would still be a bit noisy, but you probably won't need full speed with 6 in push pull.

[Korben]

I would start with 3. 6 is still double the noise... and if you think of running 6 of  them at half speed.. they would probably still sound like 3 on a normal profile  Just wasted money imo.

[Belgar]

3 minutes ago, Korben said:

I would start with 3. 6 is still double the noise... and if you think of running 6 of  them at half speed.. they would probably still sound like 3 on a normal profile  Just waisted money imo.

I want 6 because only case intake goes through the radiator first so I want to have more air to come throught, thats why I think 6 fans would be better (but its just my assumption).

[Hairless Monkey]

Just now, Belgar said:

I want 6 because only case intake goes through the radiator first so I want to have more air to come throught, thats why I think 6 fans would be better (but its just my assumption).

Push Pull is only marginally better than Push or Pull only when running high RPM, but at low RPM Push Pull will out perform Push or Pull only. So if you want silence and low RPM then Push Pull is the way to go to still get good cooling.

[Jeppes]

Dont believe the hype. Just look at the dB numbers from U12A review. And the performance difference is also tiny. Get a 5 pack of the p12 pwm pst:s from arctic for the price of one Noctua fan.

https://www.tomshardware.com/reviews/noctua-nh-u12a-cooler,6372-2.html

 

[Belgar]

8 minutes ago, Jeppes said:

Dont believe the hype. Just look at the dB numbers from U12A review. And the performance difference is also tiny. Get a 5 pack of the p12 pwm pst:s from arctic for the price of one Noctua fan.

https://www.tomshardware.com/reviews/noctua-nh-u12a-cooler,6372-2.html

 

I dont think the usecase will be the same for me, they tested it on a aircooler with a really open space. Where I would be using them in a restricted space when they need to push more air. Also for me performance>noise, but what I have problem with that even on silent NZXTdefault fans like to ramp up to 100% for a few seconds and then go back

[Jeppes]

Just now, Belgar said:

I dont think the usecase will be the same for me, they tested it on a aircooler with a really open space. Where I would be using them in a restricted space when they need to push more air. Also for me performance>noise, but what I have problem with that even on silent NZXTdefault fans like to ramp up to 100% for a few seconds and then go back

Well what you have there is a bad fan curve. Most likely you can adjust it to your liking without buying new fans for 180$.

 

 

[Hairless Monkey]

@Jeppes, @Belgar

 

Yeah that chart doesn't look relevant (it's about the stock performance of different air coolers not fans) or even very good to begin with (what does 50% speed mean?)

5 minutes ago, Belgar said:

even on silent NZXTdefault fans like to ramp up to 100% for a few seconds and then go back

It sounds like you should try setting a custom fan curve before buying new fans.

[Belgar]

2 minutes ago, HairlessMonkeyBoy said:

@Jeppes, @Belgar

 

Yeah that chart doesn't look relevant (it's about the stock performance of different air coolers not fans) or even very good to begin with (what does 50% speed mean?)

It sounds like you should try setting a custom fan curve before buying new fans.

It is but with OC it runs really hot really fast and I dont feel comfortable running CPU at 85C during load under water, plus it heats everything else since rad is at the intake

[Tristerin]

As someone running 10 Arctic P12's in his loop at full blast (push pull on 3 radiators) - I concur with going with those to save a buck, the sone they produce is mild and pleasing.

 

Noctua is quite an investment.  Arctic P12 value packs can be found between 27-30 regularly when on sale

[Jeppes]

1 minute ago, HairlessMonkeyBoy said:

Yeah that chart doesn't look relevant (it's about the stock performance of different air coolers not fans) or even very good to begin with (what does 50% speed mean?)

It sounds like you should try setting a custom fan curve before buying new fans.

It tells you that a pricey Noctua fan makes the same noise as a 6-7€ fan running about 2000rpm through a heat sink. Are you basing your expectations of performance being different with a radiator on hype or some actual tests?

[Belgar]

2 minutes ago, Jeppes said:

It tells you that a pricey Noctua fan makes the same noise as a 6-7€ fan running about 2000rpm through a heat sink. Are you basing your expectations of performance being different with a radiator on hype or some actual tests?

I mean what he sent is not even the same fans as I mentioned I was thinking about buying so your point is kinda invalid

[Grabhanem]

My 2C as someone who runs NF-A12x25s on a radiator: they're worth it. I'm on a pretty small radiator setup (240 for both CPU and GPU) and with proper fancurves my fans are barely audible under load.

 

I don't think push/pull is worth the extra $90 tho, three fans even through a radiator will give plenty of case airflow especially if you have proper exhaust fans.

[Hairless Monkey]

23 minutes ago, Jeppes said:

It tells you that a pricey Noctua fan makes the same noise as a 6-7€ fan running about 2000rpm through a heat sink.

It's a different heat sink and will have a different effect on the noise, "50% fan" means literally nothing, and the test was designed to compare air coolers, not fans.

 

The best way to directly compare the fans would be to test them against each other running at the same RPM in open air, and on the same heatsink at the same noise level with the same heat load. AKA do science and actually control some variables.

 

The test as described cannot be used to compare the noise levels nor the performance of the fans.

23 minutes ago, Jeppes said:

Are you basing your expectations of performance being different with a radiator on hype or some actual tests?

My hypothesis is that a Noctua fan will perform better under a noise normalized test on the same heatsink, or will produce less noise at the same RPM, but I make no such claim since I'm too lazy to see if any such test has been performed. 

 

The Arctic fans are fine and a good value from what I see others say.

29 minutes ago, Belgar said:

It is but with OC it runs really hot really fast and I dont feel comfortable running CPU at 85C during load under water, plus it heats everything else since rad is at the intake

The temperature of the liquid in your loop has a direct impact on the peak temps that you will get with your CPU. Every 1°C increase in fluid temp corresponds to 1°C increase in CPU temp. The fluid tends to take a while to heat up, so if you can run your fans a little faster when idle to prevent the fluid from heating up too much you'll see improvements in temps when under load. Ideally you would set up a fan curve based on the fluid temp, and you wouldn't get those sharp ramp ups and downs in fan speed.

 

From my experience its not too hard to setup a fan curve such that your fluid temp when idle is around 1°-3°C above ambient and under load is 7°-10°C above ambient.

[Belgar]

16 minutes ago, HairlessMonkeyBoy said:

From my experience its not too hard to setup a fan curve such that your fluid temp

OMG thanks, I just looked at my fan control software and I can totally set it to fluid temp. Thats so cool thank you. Can you please tell me what should be optimal liquid temp? thanks a lot

[Hairless Monkey]

6 minutes ago, Belgar said:

Can you please tell me what should be optimal liquid temp?

It really depends on your local ambient temps. In my experience, anywhere from 1°C to 15°C over ambient would be reasonable. So if it's 30°C where you are you might see temps between 31°C idle to 45°C under load.

 

Really, what you should do is monitor and get a feel for how your system performs. Find a max RPM that you are comfortable with the noise and see if that is sufficient to keep things cool, and then setup a fan curve that slowly ramps up to that speed as the fluid temp goes up.

 

Personally, I have my custom loop setup such that my fans start to get really audible around 36°C fluid temp and it never really gets over about 38°C. I have AC so my ambient air temps are like 22-26°C.

 

And for my wife's 280mm AIO I have it setup similarly. Her fluid never gets much above 37°C

[Jeppes]

On 7/23/2020 at 5:14 PM, HairlessMonkeyBoy said:

It's a different heat sink and will have a different effect on the noise, "50% fan" means literally nothing, and the test was designed to compare air coolers, not fans.

 

The best way to directly compare the fans would be to test them against each other running at the same RPM in open air, and on the same heatsink at the same noise level with the same heat load. AKA do science and actually control some variables.

 

The test as described cannot be used to compare the noise levels nor the performance of the fans.

My hypothesis is that a Noctua fan will perform better under a noise normalized test on the same heatsink, or will produce less noise at the same RPM, but I make no such claim since I'm too lazy to see if any such test has been performed. 

 

The Arctic fans are fine and a good value from what I see others say.

The temperature of the liquid in your loop has a direct impact on the peak temps that you will get with your CPU. Every 1°C increase in fluid temp corresponds to 1°C increase in CPU temp. The fluid tends to take a while to heat up, so if you can run your fans a little faster when idle to prevent the fluid from heating up too much you'll see improvements in temps when under load. Ideally you would set up a fan curve based on the fluid temp, and you wouldn't get those sharp ramp ups and downs in fan speed.

 

From my experience its not too hard to setup a fan curve such that your fluid temp when idle is around 1°-3°C above ambient and under load is 7°-10°C above ambient.

Its close enough. And its a slippery slope for you if you dont even read the test to see what 50% fan speed meant in rpm. Also if Noctua fans and coolers are so great, why is a 30-35€ Arctic Freezer 34 duo tied with the 100€ cooler in temps and noise?

[Grabhanem]

This is my favorite chart, credit to Optimum Tech:

That's an A12x25 being competitive in noise with some of the best radiator fans on the market-- at twice the speed.

[WihGlah]

On 7/23/2020 at 2:11 PM, Korben said:

I would start with 3. 6 is still double the noise... and if you think of running 6 of  them at half speed.. they would probably still sound like 3 on a normal profile  Just wasted money imo.

 

That's about as wrong as it's possible to be.

 

Correct would be the exact opposite of this.

 

I have 14 Noctua fans in my system. I can't hear any of them. They never have to ramp up, despite running a 9900K at 5.3GHz and a 980ti at 1530MHz. 

 

Having lots of rad space and lots of fans is how quiet systems are made.

 

Loudest thing in my system is the D5 pump. Which runs at setting 2.

 

 

Also - can confirm Noctua A12 x 25s are way better than any other fan for performance  / noise.

 

 

 

 

[Belgar]

Yeah so I did a thing, bought 6 NOCTUA NF-A12x25-PWM and the difference is pretty jaw dropping for me, not even my AIO liquid temps went down from 36 to 30 C but overall those fans push way more air through system hence the whole system in cooler. My rams dropped about 15C on average  

[LazyTurtle1990]

On 8/23/2020 at 3:18 PM, Belgar said:

Yeah so I did a thing, bought 6 NOCTUA NF-A12x25-PWM and the difference is pretty jaw dropping for me, not even my AIO liquid temps went down from 36 to 30 C but overall those fans push way more air through system hence the whole system in cooler. My rams dropped about 15C on average  

I see this is quite old, but i have to ask, do you use the fan as exhaust or intake on your radiator?