Alright good points, I actually forgot to mention that my tower is considered a medium one, not a high one so my motherboard is huge, causing my tower to not have space for extra fan cooler on the top spot.
The tower I have;
http://www.coolermaster.com/case/mid...-k350-kwn2-en/
I have 4 fans in total installed.
One in the front, one in the back, one in the left side of the case all of which are 120mm and are pretty good.
As for the top one, I have 80 or 90mm one which sucks pretty hard due to the fact as I mentioned, I have no space to put a 120mm there, it hits the motherboard and there's nothing I can do about that.