case fan question

[xFuryofFivex]

most cases have a fan on the side panel,ive been told and have done this in all my builds, never really wondered why. but why have the side fan blow inward instead of outward. im assuming to make some sort of vacuum

 

[133]

most of the time its to blow cool air directly at your video card. a vacuum is created when you have more air going out of your case than flowing in. having a side fan doesn't necessarly make a vacuum effect.

 

[Nenu]

On most PC cases, the fans blowing out of the case have less restriction than the air intake fans. (often the intake fans have a case front covering them and a small air inlet at the bottom which might even be blocked by carpet if the PC is on the floor)
More incoming air will be beneficial for those affected cases.

Having colder air pumped directly to the GPU/CPU areas has got to be a good thing anyway!
I disabled my side fan (blanked the hole too) and put another 80mm fan drawing cold air in from the PCI blanking slots directly onto my graphics card.