Air cooling vs Closed loop liquid cooling

vbimport

#1

Air cooling vs Closed loop liquid cooling

Both these types of cooling are really air cooling, as in a closed loop water cooler, you are blowing or sucking air through the radiator via a single or two or three fans. But for the sake of argument, let’s call a heat sink and a fan air cooling, and closed loop water cooling water cooling.

My current CPU cooling solution is a Be-Quiet Dark Rock Pro 2, a high end air cooler. Cooling performance is excellent, and as the name suggests, it runs very quietly.
One problem with the Dark Rock Pro 2 is its very large, and covers the RAM slots. So replacing or adding RAM is impossible without first removing the CPU cooler.

I thought I would give a closed loop water cooler a try. My case (Antec P280) can only accommodate a 240mm radiator at the top of the case.
I decided on the Corsair H100i V2.
Fitting was easy, and now my RAM slots were clear. But that is where the good news ended.

My system, a SkyLake i7 6700K is overclocked to 4.6Ghz for 24/7 use.

At full load these are the comparable results.
Be-Quiet Dark Rock Pro 2 = Core temp average of 72c.
Corsair H100i V2 = Core temp average 69c
So the Corsair managed to lower the temps by 3c.

At idle
Be-Quiet Dark Rock Pro 2 = Core temp average of 22c.
Corsair H100i V2 = Core temp average 23c
This time the air cooling won.

Now for the bad news.
The noise from the Corsair H100i V2 when running at max during the full load test was unbearable to my ears, whilst the Dark Rock Pro2 at max was barely noticeable.

At idle the Dark Rock Pro2 fans are spinning at only 450rpm, and inaudible in my very quiet PC case.

The Corsair at idle was fairly quiet, but I could hear the water pump.
Not only that, but the motherboards VRM’s when using the Corsair H100i V2 were running very hot. That isn’t surprising as the only air cooling the VRM’s when using a closed loop cooler is the air being sucked through the VRM’s via the rear case exhausted fan which is really to far away from the VRM’s to be effective.

The Dark Rock Pro2 in contrast expels the air from the cooler, through the VRM’s, so the VRM’s on the motherboard are being actively cooled via the Dark Rock Pro2.

The Corsair H100i V2 was returned for a refund, and I’m now once again enjoying a quiet and well cooled CPU.

The moral of this story is.
Whilst a closed loop water cooler may give slightly better performance when compared to a high end air cooling solution, and give unrestricted access to your RAM. They make much more noise, and at least in the case of the Corsair H100i V2 and I’d expect most similar products. They won’t cool your VRM’s.

Another thing I noticed.
The build quality of the Dark Rock Pro 2 is light years ahead of the Corsair.


#2

Thanks for that experiment Dee
Great information on cooling.


#3

Do you have front intake fans on your case?
If so and you are using a push configuration that could be your problem
Air turbulence reduces cooling capability and create noise
And Yes, Corsair static fans can be noisy (really noisy)
I no longer use the top for intake for the rad
I use the front for that and leave the other spots for what they were meant for

My new system has an i7-6900k at stock (for now) and under full load hit about 37to 39 celsius
I added Noctua inline resistors, low noise adapters, and temps went to mid 40s at full load…cant hear the things now
This is with a H115

If possible try with a H80 or thereabouts


#4

All the fans in my case are exhaust fans. Even the Corsair H100i was configured to blow air through the radiator and out the top of the case.


#5

For what its worth — the H100 as an intake (push) could maybe lower the temps by 2 or 3 degrees (not worth the effort in the case of your temps )
What are you doing for air intake?
Using negative pressure?


#6

I have used a few air coolers, from Artic Cooling, Corsair and Cooler master, and I can say that they all perform very good, some of them like the Corsair A70 and the Cooler Master 212 evo were very excellent for the money that they cost, and both of them had also an excellent mounting kit, something that can be said about the artic cooling, but all of them were able to cool my i5 750 @ 3.6 and also my i5 2500K (4 or 4.2) but the push pin method that Artic used, no idea if they still use it, was horrible, you could lose the push pins, the mounting of the cooler was also based on plastic and it was prone to braking.

Now since I am reviewing also RAM, I needed to have something that would give more room, and also less hassle, so I went for the Corsair H100i GTX, and I will say that I wasn’t that impressed, staring withe plastic back plate, thankfully its not needed on the X99 motherboards, but for the rest that are on the Z series, I can say that they have one more point of failure. Speaking about points of failure, I can say that there are a lot on them when you water cool.
But points of failure were not my problem, as Wendy said, the fans were/are the reason that I dont use that system that often. They make a lot of noise, and Corsair should not include them on a product that comes with a premium price tag, so you end up having to buy new ones, something that is on my to do list.

Now, temps. Well I can say that moving away from the 212 evo to the H100i GTX there was a huge difference in temps, but I traded more noise for that, and for me more space to easily remove RAM.

I will have to say that for most users, a good air cooler is the way to go, and the only thing that can go wrong is the fan, that can very easily be changed, AIO water cooling looks nice, maybe performs better but you need a lot of space to put a 240mm radiator and in my case you need to invest another 30-50 euros for better fans that will have the same or higher push capacity and make less noise.

If i had the option now to choose between an AIO and an air cooler I would have chosen the air colling option.


#7

I just used the low noise adapters on the fans and get good temps and quiet operation.
But yeah, static pressure fans can be noisy, by their nature, so in my case the adapters worked fine


#8

I can change the RPM on the software that Corsair offers, but for that price hey should have included better fans.


#9

Yes, negative pressure. All the air intakes in my case are filtered so dust isn’t a problem. I just clean the filters once a month or whenever I remember. :slight_smile:


#10

Interesting.
Cryorig uses a small fan on top of their closed loop cooler water block to cool the components around the CPU.
http://www.cryorig.com/a-series.php


#11

I was thinking of suggesting the additional fan, though it sounds like it requires a little extra rigging (or a case with a side vent & fan mount already aimed at that area of the motherboard).

With a liquid cooling setup where the pump’s speed can be varied (maybe by a PWM fan connector), and with a different fan configuration for the radiator, it does sound like it may be a little more palatable.

But since air cooling, in this scenario, performs quite admirably anyway…it seems like a personal preference more than anything. Good to know for the future. :slight_smile:


#12

I have 1 system air cooled and 1 water side by side. The new water cooled system is noticeably quieter, even when I was running stress tests over and over with higher and higher clocks. I have heard about water coolers having air bubbles and being noisy. Could that maybe have been your issue Dee. Even at my highest stable OC I had less noise than my air cooled i7 2600k running at minimal load with a 4.0 clock.


#13

I do know on my i5-4690K @4.2Ghz the fan is more productive but if I turn OC off it is quiet but I got after CoolerMaster for it and plus I do try to clean the fins from Dust Bunnies as much as I can. This will help keep the fans from running at higher rpm to keep CPU cool. That the disadvantage to air cooling “dust bunnies” but alot also has to do with the quality of the cooling system hardware you buy and if it is better made it will be quieter then cheaper models. So the Fan themselves can contribute to the noise effect so cheap fan would be more noisier then a better designed cooling fan. So there are two parts to all cooling system the heatsink or liquid heatsink and then the fans used to cool the system down. Mine is in my room and when idling can be heard but not deafening that you can’t sleep but if you Game the GPU and CPU fan are noticeable. But once I clean the CPU fins the amount of noise does go down-can say how much but in a small room you do notice a slight decrease.


#14

You should have went with the H-105… Far better cooling than any other Corsair model (older or newer). Granted it has no monitoring software (native) but this is not a drawback at all, when one considers the nearly unrivaled cooling performance and price-point AND the very simple installation of the unit.

I run an H-105 on a 4790K @4.6GHz; idle temp 21C, max under load (gaming) avg. 48C-52C. Stock Corsair fans, stock (included pre-installed) paste used, rad top mounted with fans pulling air into (intake) case vs. expelling (exhaust). I’ve read a lot of users do this when top-mounting rads and even recommend this; IMO this a no-no as exhausting hot internal case air across the rad will increase temps by 3C - 5*C, or more esp. if running SLI.