Case fan air flow question

Me myself & him

Me myself & him

New member
I'm planning to get two new case fans (later on) and I can't decide on the direction of air flow.

I have two spots on the case, one in the bottom front and one in the back under the power supply.

The guy at the store told me to have one fan to suck cool air in from the front and the one in the back to blow hot air out.

But someone told me, it was better to have both fans blowing all the hot air out.

Are there specific types of fans that can handle all of this? My case is an ATX, I think it will only take the regular square fans.

Any feedback will be greatly appreciated.
 
I added an extra case fan (just for something to do), and tried both 'flow thru' and 2xintake fans without any dramatic change to my CPU/chassis temp.

Are you ready for the extra noise?
Is your system running hot?
Are you doing it just cause you can (I know I did)?

:)
 
Intake in the front bottom, exhaust in the upper rear. That's the way it goes. If the innards of your machine aren't obstructing airflow, and your case is properly sealed, this will provide maximum cooling.

If you have all your fans blowing out, just how is air getting in? Not only will this be hard on your fans, but you will end up with huge stale pockets of hot air. Equal numbers of intake and exhaust fans allow you to direct airflow. Simply blowing air out makes it impossible to predict airflow.

What you want is physical airflow over critical components at all times. A fan blowing air into the case does not ensure that air is circulating where you want it to be circulating. Think it through. Remember, hot air rises, cool air sinks :) Or don't think it through. Use at least one intake fan in the bottom front, and preferably one in the top rear helping out the P/S fan (if necessary). Make sure your cables are tied up real nice, and you're all set.

Slackmaster 2000
 
B1&B2 said:
Are you ready for the extra noise?
Is your system running hot?
Are you doing it just cause you can (I know I did)?

:)
Click to expand...

A little of both.

My HSF is already loud as hell.

My system was running hot...... until I burned out my CPU.:(

Though my new MOBO just arrived and I have a new memory chip and I'm getting a new processor, I still want to have maximum cooling... even if I don't really need it.:D
Hell, it couldn't hurt right?


Oh, and Slackmaster, thanks for the tip, I'll do it the way you told me to, and I'll tie up the cables... I didn't think about that before.
Thanks guys
 
Ditto with Slack. It's also a good idea to try to set up one fan so it is blowing across your CPU.
 
You mean a third fan? I would have to either put it on the bottom of the power supply or find somekind of way to connect it to the inside of the top of the case... real hard to figure out.
But I don't really have a place to attach them there.

Any Ideas?
 
Me myself & him said:
You mean a third fan? I would have to either put it on the bottom of the power supply or find somekind of way to connect it to the inside of the top of the case... real hard to figure out.
But I don't really have a place to attach them there.

Any Ideas?
Click to expand...

I'm not sure this is what RWhite meant, but there's actually a whole case-modding scene out there for this kind of stuff. You can just get a Dremmel and go to town! One popular mod is to mount a "blowhole" fan in the top of the case. It's a really good way to release the hot air that accumulates up there.

I've got a plexiglass window in the side of my case so I can watch all the fans go round. Now I just need one of those neon lights in there. :)
 
3 fans in MY system.

One on the CPU blowing upward.

One blowing in through a filter element.

One blowing out through the Power Supply.

Works for me.
 
You would recommend drilling through the top of my case?
I'm worried that would void the warran-............. oh yeah, I don't have a warranty:(
 
No! those are extreme do-it-yourselfers. Stick with the One fan in the bottom front blowing in and the other in the top back blowing out.
 
Sorry Me Myself,

I was just taking the opportunity to spout off about what a geek I am. There's nothing worse than a geek that doesn't know he's a geek.

You'll probably be fine with one in the front and one in the back.

If you're concerned about noise, these guys have a pretty good selection of low-noise fans:

http://www.directron.com/silence.html

Good luck man!
 
Thanks for the link.

Hey, I'm a little confused about those box-fan things, should I stay away from those if I already have a power supply?
 
I believe those are power supplies you're talking about. I wouldn't worry about those unless the one you have is too loud for your needs or has insufficient wattage.
 
Naah, I'm sure mine is OK. But after I get my new processor, I'll have about 30 dollars to get the case fans with. Should I wait and get some more expensive ones, or will a couple of 14-15.00 ones do?

Also, What is a pretty good fan speed?

What do you think of the noise reduction stuff, silencers?
 
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You should be able to get a couple of good fans for $30.

As far as fan speed goes, I think that's more a function of the size of the fan and the voltage applied to it. Just make sure you get the right size fans.

Here's a good forum for learning about these kinds of things:

http://www.amdforums.com/forumdisplay.php?forumid=18

edit: I think it's probably cheaper and more effective to just buy quiet components in the first place rather than try to silence 'em later. I don't have any first hand experience with any of those products.
 
Don’t laugh but I think I heard of a super geek who put some air conditioning apparatus in his computer. I think he was over clocking to extremes or something. One of my geek friends told me about it.
 
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