Question new case fan

hardcore_gamer29

Senior member
Jul 24, 2013
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i have corsair 780T which has two front intake fans and one rear exhaust fan. Now i want to add two 120mm fans on bottom . What should i make them intake or exhaust. On top i have 360mm AIO exhaust
 

Fallen Kell

Diamond Member
Oct 9, 1999
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Intake, but make sure you have dust filters on them. Typical best cooling for a case will be bottom->top and front->rear airflow. This has the added benefit of following basic thermaldymaics of gasses under gravitational pull, wherein the hot air will naturally want to rise up...

The reason for the dust filters is due to the bottom of a case being one of the most likely areas to have and accumulate dust from the general environment.
 
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Stuka87

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Dec 10, 2010
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Testing has shown that 'heat rising' has absolutely no impact on case cooling. The orientation of the fans is best determined by the design of the case, and the GPU and CPU cooling solutions.

Being that the 780T has its PSU on the bottom, can you still place two fans down there? Do you have the 3.5" drive bay removed maybe?

Anyway, the best solution for that case tends to be having the front fans as intakes, and the rear and top fans as exhausts. This keeps the air moving in mostly one direction, and wont suck up dust and stuff off your desk.

EDIT: I just noticed you said you had an AIO up top. In which case, are your case temps getting too high? Six fans (seven if you count the PSU) should really be enough, especially with CPU heat not being inside the case.

1626128401915.png
 

hardcore_gamer29

Senior member
Jul 24, 2013
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Testing has shown that 'heat rising' has absolutely no impact on case cooling. The orientation of the fans is best determined by the design of the case, and the GPU and CPU cooling solutions.

Being that the 780T has its PSU on the bottom, can you still place two fans down there? Do you have the 3.5" drive bay removed maybe?

Anyway, the best solution for that case tends to be having the front fans as intakes, and the rear and top fans as exhausts. This keeps the air moving in mostly one direction, and wont suck up dust and stuff off your desk.

EDIT: I just noticed you said you had an AIO up top. In which case, are your case temps getting too high? Six fans (seven if you count the PSU) should really be enough, especially with CPU heat not being inside the case.

View attachment 47035
in india here, in summers temperature rises till 45 degrees, my motherboard temperature was like 46 i saw a few days ago thats why i am worried. yes, i have removed all cages from bottom and front fans came as intake default
 

Stuka87

Diamond Member
Dec 10, 2010
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in india here, in summers temperature rises till 45 degrees, my motherboard temperature was like 46 i saw a few days ago thats why i am worried. yes, i have removed all cages from bottom and front fans came as intake default

46 for the motherboard in high ambient temps isn't all that bad. But, if you are ok with the added noise, and you have some filters for the new bottom fans, then add them (as intakes). You would not want them as exhaust with the fronts being intake, as they will draw out a lot of that fresh air before it can get to some of the other components.

And its important to have filters as they will pull anything that is on the desk up into them.
 
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aigomorla

CPU, Cases&Cooling Mod PC Gaming Mod Elite Member
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most important question on bottom fans is:

is your case on the floor or on the desk?
If its on the floor, do not use the bottom fans.
They will either throw dust all over the place if you have them exhaust back, or all the dust will get pulled in if its set to draw in.

If its on the desk, then its another set of questions.
 
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hardcore_gamer29

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Jul 24, 2013
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most important question on bottom fans is:

is your case on the floor or on the desk?
If its on the floor, do not use the bottom fans.
They will either throw dust all over the place if you have them exhaust back, or all the dust will get pulled in if its set to draw in.

If its on the desk, then its another set of questions.
yes it is on desk not floor
 

aigomorla

CPU, Cases&Cooling Mod PC Gaming Mod Elite Member
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yes it is on desk not floor

then how dirty is your desk habits... honestly.
If its dirty, then have them blow out, and it will keep your desk somewhat desk free.
If you run a clean desk, then have them blow in.

Honestly Orientation will not matter much on bottom fans unless its directly facing the gpu.
Its mostly dependent on case location for bottom fans.
 

hardcore_gamer29

Senior member
Jul 24, 2013
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then how dirty is your desk habits... honestly.
If its dirty, then have them blow out, and it will keep your desk somewhat desk free.
If you run a clean desk, then have them blow in.

Honestly Orientation will not matter much on bottom fans unless its directly facing the gpu.
Its mostly dependent on case location for bottom fans.
have a bad habit of blowing the pc once in a month
 

BonzaiDuck

Lifer
Jun 30, 2004
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JOKE: Do you mean the PC has a redacted? I know what you mean -- canned air or a Metro blower.

I would expect parts of India to have a hot climate. And maybe 45C is normal. But to me, 110F or higher is pretty damn hot. The whole world is heating up.

Enjoy your gaming, your favorite meals, your cool evenings -- when you can.

I wouldn't use bottom case-panel fans for exhaust. I would use them for filtered intake. And if I were to use them that way, I'd buy 2.5" braked-caster-wheels to give the tower case some mobility and raise the case above the floor or even the desk surface another 3 inches. Then, you have unobstructed intake air. But it should be filtered.

Profanity is not allowed in the tech forums.

AT Mod Usandthem
 
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