DescentBB

Well, so I finally bought my new Core i3 2120 Rig and everything is goin' pretty sweet, in general.

As I bought it, it only has the CPU fan and the PSU fan, and I get pretty decent temperatures overall according to the monitor software: 26° for idle cpu, 53° for heavy CPU use (60%) and 60° for extra-heavy CPU use (88%~).

The overall system temperature is always around 34°.

But I would like to buy some extra fan to have the system at an even better tempreature.
The case includes two slots for two 80mm fans, one at the back and one at the side.

I don't have a Video card except for the integrated one, so I suppose for now a side fan wouldn't be so neccesary, so I would like to go for a back fan (maybe a 2000rpm one).

So, the real question is the next one:

Should I put the back fan as an exhaust fan or as an intake fan?
Which one of those modes is better, pulling air out of the case or putting air into the case?

Either way works, which one is the most effective depends on the layout of the case. A common method that is pretty effective is to draw air so it flows through the entire case from the front to the back. But honestly with your temps, I don't think there is much room for improvement without switching to a larger CPU heatsink. Perhaps a better idea would be to check your hard drive temps and target some fans on them to reach a better operating temp (aim for ~35-40C for a mechanical HDD).

OK, will take your advice in account.
Thanks for the enlightenment on the issue once again Krom!