Cooling fans

Hey folks,

got a little q about my build. I used to have problems with my heating, but I build in a watercooler and all is well… But I still have room for some more cooling fans and I was wondering if it is the smart thing to do to build in some extra cooling.

Right now I have a big fan in front venting out, a double fanned watercooler and a medium fan in the back venting out.

I still have room for 2 more fans and was wondering if I should build them in at all and if I do, if I should let them vent in or out.

More fans will never hurt (though they may not be necessary) assuming they are set up properly (assuming you don’t mind the added noise).

Under ideal circumstances you should try your best to balance the air flow (same air flow in as air flow out).
This would result in the best cooling for your system.

Large (240 mm fans) generally do quite a lot of work in terms of air volume transfer.
A safe bet is 2 standard size (120 mm) venting out to balance the incoming air from the larger fan (PS: i would suggest flipping your front large fan so that it is an intake). It looks like your radiator fans probably already perform this task (radiator fans should be exhausting air out of the case whenever possible).

This means your single back fan is likely creating a small imbalance where more air is being pushed out of your case than is being pulled in.

I usually like to have a slightly positive balance (meaning I am pushing more air into the case than out of the case) - I have noticed on my case (CoolerMaster HAF) this usually helps with preventing dust buildup in locations that are a P.I.T.A. to clean.

I might suggest configuring your two new fans in an intake position.

Other opinions follow the premise of thermal expansion of air - wherein the hot air you are expelling takes up more volume than the cold air you are taking in. People who value this thought process will have more exhaust fans than intake fans. However, those people fail to consider the minimal amount of expansion that is taking place in my opinion.

Anyway - TLDR: I would say make them intakes - but more air flow one way or the other wont hurt.

Just make sure your intakes are low and your exhausts are high =)

Just my 2 cents - opinions may vary

I second what Infandus said. You should look into changing the direction of one of your fans.

First things first. What part of the case is your double fan liquid cooling radiator sitting at? I’m assuming you also have the double fans on the liquid cooling heat exchanger facing outwards as well. So you’ve got a net 4 fans going outwards. In an ideal world you want the air to flow through your case. But if all you do is have fans vent outwards they are going to fight against each other and in the extreme scenario if your case was air tight all you would get is a vacuum inside.

I’m by no means a pro, but I have done fire modelling and heat transfer calculations in college and nowadays have been involved with room integrity tests for clean agent fire suppression systems. I’m personally a fan (pun intended) of mounting the intake fans on one end of the case near the bottom. Doesn’t really matter front or back so long as your intake area around the case in unobstructed. Then on the other side mount the exhaust fans higher up. Heat likes to rise and although it won’t make a huge difference, if you want every cent to count, you might as well work with that natural upwards movement.

From what you’ve described, if I were you I would mount that double fan heat exchanger and vent it outwards. It will already have picked up heat from the liquid and it isn’t a bad idea to force that hot air coming off the cooling fins out of the case rather than across the components you’re trying to cool.

Of course you can argue that the ambient temperature inside your case will be inherently warmer than the air in your room so your liquid cooler won’t have quite as good of a starting temperature. I still prefer it though since the alternative means your liquid cooling would be exhausting inside your case and you’re effectively forcing hot air directly back onto the components you just cooled.

Also as far as adding more fans. If you’re not overheating right now with your current setup then I wouldn’t bother. Get a temp monitoring software and check out your numbers. I’d be willing to bet you’re more than fine. At the ending of the day all you’re looking to do is keep your PC cool, not turn it sub-zero for improved conductivity of a supercomputer. 9 time out of 10 you’re just adding unnecessary airflow and airflow = noise. Also Keep in mind that the smaller the fan, the more it has to turn to move the same quantity of air. Your ears will thank you if you have fewer large diameter fans at a lower RPM

The other thing people almost always forget to think about is power consumption. Your electronic components are never 100% efficient and the byproducts in the case of a PC is heat. When you’re shopping for your next CPU or video card, check its power consumption. Lower wattage means less heat generation which nets you less need for noisy fans. I’m not very in tune with current AMD and Intel processors, but back in the day AMD had a reputation for being quite power hungry.

Hope that helps a bit. Sorry for the novel.

thanks guys…

and yes my AMD cpu is very power hungry and produces a lot of heat… although I like its performance I will go intel next time…
Its nice AMD is cheaper then intel for the intitial buy, but when you consider the corst of a decent liquid cooler and all I am not sure its worth it.

But for now its performing great, so no reason to switch to intel yet

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