Front case fan vs Rear exhaust fan!!!

[sundarpn]

i have a mid atx tower(300w), running an athlon 650 with all usual cards (agp, snd, mod,netwk) on abit ka7-100. athlon has retail h/s and fan. runs at abt 44C after a few hrs.

the case does not have an opening for a rear exhaust fan, but has one for a front case fan.

I was just wondering if i should remove the additional port covers on the back (approx behind the processor) and put a rear exhaust fan, or will the front fan which blows air into the case be better.

thanks

 

[Mikewarrior2]

front case fan, especially since it appears you don't have any intake for your case right now.



mike

 

[Toro 45]

Case fan for the front & a slot fan to exhaust out the rear.I've compared temps in a case similar to yours & the rear exhaust always made a bigger difference than the front intake.But like I said both would be best.
Toro

 

[rpr]

Gettting the hot air out will always make a bigger difference than just trying to get cool air in.

 

[Mikewarrior2]

yes, i agree you need to get the hot air out, but if the only fan in your system is the power supply fan, then, at least get the front intake going... DO not ignore the front intake fan



Mike

 

[gtd2000]

Nope I disagree - rear top exhaust fan - I have this in my system it made the biggest difference (temperature drop) of all on my old overclocked 450A system.

Front intake fan just made an unbearable noise and only pumps the air in.

If you blow the hot air out of the top of the case you suck cool air in from the bottom - I can see that works well from the dust gathered in the various corners at the bottom of my case

I tried all posibilities - but the single exhaust fane made the greatest drop in temp.

Try for yourself see what happens in the various positions

 

[LarryJoe]

The rear case exhaust fan made a huge difference for me. I have an Enlight 7237 which came with a front-in and ps fan only. After installing the rear exhaust fan, my temps dropped by 10C.

LJ

 

[Mikewarrior2]

Well, first off, a front case fan does not usually create an unbearable noise..

And secondly, if all he does is cut out a hoel for exhaust, his case is going to be completely dusty. I'm not telling him to ignore Exhaust.. hell, i have 2 80mm exhausts, nad 2 92mm exhausts. But since he has an opening for a fan, and it "won't" be noise if installed properly, he should at least do that.



Mike

 

[klock]

I remember when I was O/Cing my 300a/450 2 years ago, I tried installing the rear fan forward (sucks cold air in) and backward (sucks hot air out). The difference was huge between those two setups the mb temperature different was approximately 15C. Just my 2c.

 

[sundarpn]

thx for ur views. i have put the fan in the front (below the speaker where the intake openingf is there) into the cup like thing which takes it.
as my case doesn't have an opening for rear exhaust fan, i am going to remove those additional tabs which are there for the ports right behind the athlon, and am going to secure the fan to blow the hot air out. i feel this will be better, that askin the fan to blow air in.
to get air in the openeings inthe front should be enough.

i'll keep u guys posted.

 

[Mday]

you really should have both.

 

[Quickfingerz]

You really don't need both. Not at all. The only worry is that your PS fan will steal some air that would normally would flow out of the power supply. If you are going to get an exhaust fan only, make sure the exhaust fan isn't that much stronger than the power supply fan.

 

[EmperorNero]

I agree w/ mikewarrior on this - don't ignore that front intake fan. you will need some source that will suck in cooler air. if you have too much air blowing out, and not enough blowing in, your case will become a vacuum. then it'll start sucking in air from any space possible. the result? heat problems and a hell of a dust case. you should utilize that intake fan. here's a little site to create a home-made filter:

http://www.ipkonfig.com/Articles/FanFilters/FanFilters_01.htm

but you will also need an exhaust fan too. so take all of your components out of your case. then remove the top if you can. if you're uneasy about cutting a big hole into your case, you should then drill a bunch of little ones that would provide enough air flow to attach a fan there. someone else will probably elaborate on this.

 

[Quickfingerz]

Wrong, a vaccuumed case will produce less dust. I can guarantee you on that. Try it yourself. Having a intake fan is not important. If you aren't using a case intake fan make sure you have a nice vent where air can easily get in.

 

[gtd2000]

Mikewarrior2
The reason I got lots of noise was due to the air being sucked thru the front panel of the case - hell of a racket - not from the actual fan itself!
I basically opened up all the spare slots at the rear top and inserted a fan - very cheap and very easy to install...
The main thing you want to avoid is stagnant air inside the case...a flow of air is what you are trying to achieve ....whether this is by sucking or blowing (ooh err!) doesn't really matter.
However if the air in the room is warm - won't really make much difference overall...

 

[Oldsalt]

The amount of dust inside a case is directly related to the exhaust CFM no matter how the air gets in. The ideal cooling using fans; the intake CFM should equal the exhausted CFM. The above has been proven in aircraft systems for years. Another point, air can be pulled easier than pushed.
One thing I have found that helps is locate a fan about 3 inches above the case floor blowing upwards/vertical flow.
os