Which way should my case fans blow??

[Vertech]

I'm going to build my first computer this summer (around July 4th, hope for some big sales at NewEgg and prices drop) so I'm going to ask a question ahead of time. I'm going to buy the Chieftec server case with 3 fans ( two in the back and one on the side panel

1. For the best use of those 3 fans, which one should blow out and which one should blow in?

I'm thinking of having the side panel one blow in to cool video card and pci cards. For those two fans in the back, one suck the air into the case, the other blow it out

[setfree]

If the fans in the back are close together I don't think it would be a good idea for them to be blowing in opposite directions. It wouldn't be very efficient since one would be exhaust the air from the other one. If you have two close by each other then they need to be pushing air in the same direction. As for which should be intake and which should be exhaust, it all depends on the size of your case, how much air the fans actually move, etc. It's more a matter of experimentation. I would recomend trying different configurations. Try the fan on the side as an intake first with the other two as exhaust. An ideal fan setup would be if you had a fan in the front of the case that could bring air in. However with only three fans your going to have to try different configurations and see which one works best.

[juppy]

Yes, definitely DON'T have the two on the back blowing different directions. As said, it would be better if you can mount one of them down front, but if there isn't a slot in the front then put both of the back fans blowing out (exhaust). The side fan I've heard done both ways but I think most of 'em blow into the case (intake). If you have both fans on the back exhausting plus the power supply fan is an exhaust, the side fan would probably do better as an intake anyway. Just trial and error really....see what give you the best temps. :)

[Byte 2.0]

Yes you really need good intake as well as exhaust. I would probably make the all in the back exit and the side and front intakes. If the ones in the back are not very close, you my want to make the bottom one an intake.

[Vertech]

Yes, my case has a slot in the front the fan. So I'm going to take one from the back and put it in the front as you say. I might buy another fan, but i'm a little scare of the "jet noise"

I want my ears to stay healthy for quite a long time :)

[Spyda]

i had 1 fan in the top back, 1 fan in the bottom front and 1 fan on the side.

I moved the front fan to underneath the top fan in the back and i get lower temperatures and all the components literaly feel cooler.

I just had to make a slight modification in the front, which isnt even noticeable on the outside and i can feel the airflow being dragged through the case, and getting air pulled through the case is way better than air pushed into the case

[Cricket]

I'd install 2 fans on the back for exhaust (blowing out) and one on the side as intake to blow on the cards. Since there is more exhaust than intake, there'll be negative pressure in the case and this will naturally draw air into the case through the front fan openings. And with no fans on the front of the case, your computer will run a little more quietly.

:) Cricket

[Vertech]

Good points Cricket and Spyda, I think I'm going to set my fans like that.

[Propain]

I got one Thermaltake 80x80x25 High Performance DC FAN at the rear sucking air out, Thermaltake Highest Performance SMART & SILENT VOLCANO 9 Cooler http://www.thermaltake.com/products/heatsink/v9.htm and 2 Sunbeam case fans on the side panel shooting air IN on my video card and the other on the chipset and cpu.

cheers and good luck

[Nuclear Krusader]

Courtesy of BFD Deadeye. This diagram shows different orientation of the fans and the temps gotten with each one so you can see which is better:

http://www.3rivers.net/~randshan/Case%20fan%20test.bmp

(BMP image so the page will be kinda slow to load)