cpu cooler blowing out the top or the back

[Doougin]

Is there benefits to having it one way or the other. My case is a Haf 912 and my main concern is when its blowin out the back it pulls some air thru my fan controller on the front and dust builds up in it. Im just lookin for some input on this as im still kinda new to building computers.

 

[fffblackmage]

If you have a negative air pressure inside the case, you'll be getting dust building up on your fan controller regardless of which direction you point the cpu fan.