[SOLVED] Is top mounted exhaust fans adviced?

Mr Drummer

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Sep 21, 2015
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Hi, just built a new PC in the ”Corsair 4000D Airflow” case. I took out the from mounted 120mm fan though and added two 140mm fans from an old Fractal Design Define R5 case instead for a total of 3 fans (two intake fans in the front and one exhaust fan in the back). I’ve got two more Fractal Design fans though from and old ”Core 3300” case and wonder if it is adviced to have on or two exhaust fans mounted at the rop of the case aswell? I mean the temps are fine but if i have two fans just lying around and it would affect both the air pressure and temps in the case positively why not use them.
 
Solution
Since you have extra fans, you have the means to experiment.

But, I think I would not.
Normally, you want the front air intake to flow over the motherboard and gpu as well as through the cpu cooler and out the back of the case.

Top fans tend to divert the front airflow out the top without doing much cooling.
Since you have extra fans, you have the means to experiment.

But, I think I would not.
Normally, you want the front air intake to flow over the motherboard and gpu as well as through the cpu cooler and out the back of the case.

Top fans tend to divert the front airflow out the top without doing much cooling.
 
Solution

carocuore

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Jan 24, 2021
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Depends.
If you're using a founders 3090 and let's say an AIO for your CPU with the rad mounted at the front you want all of that heat to exit the case quickly, and top exhausts are the best way to do it.

I have graphics card that blow all of the heat thru the back and into the case and it gets really hot in minutes, 2 140mm fans on top solved my problem and temps dropped by about 10 ºC.


tl:dr? depends on your specs
 

Mr Drummer

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Sep 21, 2015
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Depends.
If you're using a founders 3090 and let's say an AIO for your CPU with the rad mounted at the front you want all of that heat to exit the case quickly, and top exhausts are the best way to do it.

I have graphics card that blow all of the heat thru the back and into the case and it gets really hot in minutes, 2 140mm fans on top solved my problem and temps dropped by about 10 ºC.


tl:dr? depends on your specs

I’ve got an old GTX 980 Ti (MSI B550-A Pro, 3700X + Noctua NH12P with one fan in push config mounted at the front), Just put in a new PSU today so i thought since i where going to muck around i the case anyway it would be a good opportunity to add extra top mounted fans if it would improve the general airflow and temp. If it won’t do much i’m gonna skip that for now though.
 

Windows22

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Dec 30, 2020
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Since you have extra fans, you have the means to experiment.

But, I think I would not.
Normally, you want the front air intake to flow over the motherboard and gpu as well as through the cpu cooler and out the back of the case.

Top fans tend to divert the front airflow out the top without doing much cooling.
I agree there, hot air after all rises.