side fan in or out?

[realredpanda]

i have two fans in the front of the case blowing out and two fans in the back blowing in,which way should i have the side case blow,in or out?also i have a pci fan blowing up to the video card and my psu gets abit hot,powmax 580watts(yes its overkill,but it lights up!).

 

[HardWarrior]

The front fan should be intakes (especially if they're mounted low), and the rear ones should be exhausts. The idea is to move air across the mb and out the back.

 

[LeetestUnleet]

Originally posted by: HardWarrior
The front fan should be intakes (especially if they're mounted low), and the rear ones should be exhausts. The idea is to move air across the mb and out the back.

And in that ideal case, the side fans should be intake, and any top fans should definitely be exhaust.

 

[Rastus]

I have:

2 front intakes
2 side intakes
Power supply is intake
2 back exhaust
1 top exhaust

All of the intakes are filtered.

That makes for 5 intakes and 3 exhaust. Therefore there is a positive pressure inside the case (relative to ambient air pressure. With positive pressure inside the case, there are more air molecules hitting the internal fans (CPU, GPU and hard drive cooler). It makes those fans run marginally slower, but they are more efficient. It also makes the heat transfer from heatsinks more efficient, thus your whole system and individual components run cooler.

As a side note, if you have negative pressure inside your case, your internal and exhaust fans run faster and have a much shorter life. I know this because I service about 100 386 and 486 industrial computers (they still make them) that have AT power supplies that exhaust but there is no intake. The power supply fans last about three months and the power supply heats up and shuts down. You can power cycle it a few times, then after about a year, the power supply is toast.

 

[HardWarrior]

Originally posted by: LeetestUnleet

Originally posted by: HardWarrior
The front fan should be intakes (especially if they're mounted low), and the rear ones should be exhausts. The idea is to move air across the mb and out the back.

And in that ideal case, the side fans should be intake, and any top fans should definitely be exhaust.

Exactly the way my box is configured. :thumbsup:

 

[realredpanda]

thank you all for the info,i'll reset my fan's tonight

 

[realredpanda]

turned them all around and the case temp droped 4c from 22c to 18c,the cpu also droped a few c.thanks once again

 

[HardWarrior]

 

[Nebor]

Originally posted by: Rastus
I have:

2 front intakes
2 side intakes
Power supply is intake
2 back exhaust
1 top exhaust

All of the intakes are filtered.

That makes for 5 intakes and 3 exhaust. Therefore there is a positive pressure inside the case (relative to ambient air pressure. With positive pressure inside the case, there are more air molecules hitting the internal fans (CPU, GPU and hard drive cooler). It makes those fans run marginally slower, but they are more efficient. It also makes the heat transfer from heatsinks more efficient, thus your whole system and individual components run cooler.

As a side note, if you have negative pressure inside your case, your internal and exhaust fans run faster and have a much shorter life. I know this because I service about 100 386 and 486 industrial computers (they still make them) that have AT power supplies that exhaust but there is no intake. The power supply fans last about three months and the power supply heats up and shuts down. You can power cycle it a few times, then after about a year, the power supply is toast.

You use your power supply as an intake? That's interesting. I mean, a good idea for saving the power supply, but I've never heard of that being done before.

 

[MikePanic]

side fans should be intake and top (port hole) fans should be exhaust... as stated

however, depending on where your side fan is mounted, you may ruin all airflow w/ the case as it may compete w/ the cpu fan and thus mess up the front to rear airflow

ive always been a fan of just front and rear fans, and if you still need to drop the temps a bit more, then go porthole to free up some of the hot air stuck at the top of the case from 5.25" drives and the ps

 

[Rastus]

You use your power supply as an intake? That's interesting. I mean, a good idea for saving the power supply, but I've never heard of that being done before.

I was wrong about ATX power supply fans being intake. They are exhaust.

Therefore, my main rig has 4 in and 4 out. It is balanced, which is good. However any unbalanced breathing by your computer should shade to the positive pressure side.

 

[jswjimmy]

Originally posted by: Rastus
I have:

2 front intakes
2 side intakes
Power supply is intake
2 back exhaust
1 top exhaust

All of the intakes are filtered.

That makes for 5 intakes and 3 exhaust. Therefore there is a positive pressure inside the case (relative to ambient air pressure. With positive pressure inside the case, there are more air molecules hitting the internal fans (CPU, GPU and hard drive cooler). It makes those fans run marginally slower, but they are more efficient. It also makes the heat transfer from heatsinks more efficient, thus your whole system and individual components run cooler.

As a side note, if you have negative pressure inside your case, your internal and exhaust fans run faster and have a much shorter life. I know this because I service about 100 386 and 486 industrial computers (they still make them) that have AT power supplies that exhaust but there is no intake. The power supply fans last about three months and the power supply heats up and shuts down. You can power cycle it a few times, then after about a year, the power supply is toast.

so thats what happened to my old p2 system, and all this time i thought it was the mobo. i guess i can sell the old se440bx2 now.

 

[RussianSoldier]

I'm thinking of isolating my PSU from the rest of the case, and cutting a hole in the top for a fan...

 

[0roo0roo]

easier to get a fan speed controller, you can then balance airflow or create whatever pressure difference you want. psu blowing in is stupid, adding a ton of heat to the case.