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I wonder if anybody has thought of this...

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Jun 14, 2001
I'm sure what I'm about to post has been done, but I'm curious as to what you guys think.

What kind of difference would fans on TOP of the computer make on the case temp? I was figuring, since heat rises, if you were to make a few holes on the top part of the case, put some strong fans on there that would suck out the heat, new, cooler air could make it's way through from the bottom. Would that work? Has anyone here ever tried it? Now that would be interestin... :) Any thoughts comments??

Yup, I have that setup too but basically I didn't bore a hole at the top of my case but instead installed a 80cfm twin centrifugal fan at the topmost 5.25" drive bay. Left the PCI slots uncovered so that the cool air comes in from below.
BTW, the fact that hot air rises and cold air descends have very little to do with this way of ventilation your case. The airflow going thru your casing due to the fans is so much stronger than natural convection due to different densities of air at different temps and is a negligable component of the airflow.
Yes.. I run five 120 mm fans in my full tower running of a seperate PSU. Three provide cool air, One is connected to a funnel over the CPU and One is and exhaust at the top of the case. This creates slightly positive pressure within the case which keep the air moving which helps remove hotspots.
UnseenMenace (Jul 01, 2001 05:02 a.m.):
Inside every overclocker is a little demon and every time you bend over a PC that lilttle demon wispers in your ear "how fast can you make this thing go before it begs for mercy?"

God I hate that little voice! It's not so bad when it starts wispering in your ear when your at your own PC. But it seems to start wispering when I'm on everyone else's as well. Parents, Inlaws, Friends. I've tried overclocking all there system's just to see if I can without them knowing! I know I'm bad!

As far as the exaust at the top goes. Thats why your PSU sucks air out of the case. For that same purpose. to cause good stream of air to flow from bottom to top. That way it in contact with all your hardware. But that alone is not nearly good enough. I'ts a must to have a fan on the bottom for intake.
When I built my dads pc, his cpu temps were around 50c @ idle (T-Bird 1.2 gig w\ super mini orb). As soon as I cut a hole in the front bottom of the case so the 80mm fan had more room to breath his temps dropped down to around 39c @ idle. Of course I alway stick another fan in the top back for exhaust purposes. With that setup you'll get better results with the side of your case on, And all other holes sealed up. Atleast I do.