Up or down for the round-and-round?

March 14, 2007 10:39 PM

When installing a power supply does the second fan/grill that is inside the case (not the 'back' power supply fan) face up or down?

Im having trouble fitting it into my case fan up, but I thought thats the way its supposed to go... however if its facing down the fan is blowing directly onto the cpu/cooler... I'm worried that installing it face down will blow hot air onto the CPU? Or is it supposed to be face down? thanks :)

posted by Satapher to Computers & Internet (4 answers total)

Computers generally take in air in the front or from the sides and blow it out the back, so your power supply will actually be taking the air that is flowing over your cpu cooler and blowing it out the back of the case.
posted by jjb at 10:47 PM on March 14, 2007

I suppose I should have said that you'll want to install that power supply with the fan down to the cpu cooler.
posted by jjb at 10:48 PM on March 14, 2007

Response by poster: thank you, however i just wasted a question... i tried it fan facing down again, and kinda had to force it over to the left a bit and viola! the screws lined up perfectly :) I also realized in that same instant that the back fan was the exhale and the inside fan was the inhale :) thank you tho!
posted by Satapher at 10:50 PM on March 14, 2007

Down.

I dont think it should be blowing onto the cpu, are you sure it's blowing and not sucking?

The power supply should always suck air from the case and exaust it outwards. For proper circulation, ideally you will want to place fans at the front-bottom of the case that suck air into the case.

Also more air going into the case than coming out is better(positive pressure in case), as it prevents dust from being sucked in through tiny gaps around your case.
posted by Sonic_Molson at 11:59 PM on March 14, 2007