I already asked the case modifier of the above about this. I just want a 2nd opinion. From the top photo: the PSU fan is on the right. It is sucking air IN. So it is sucking in the warm air within the case along with a small amt. of ambient air at the gap between the case. The bottom photo is the other side of the case. You can see there is a large opening there at the top, that's where the PSU is sucking the air from the case. The ONLY fans to draw cool ambient air in IS the front fans, where you can put 3 x 120 mm fan, as well as the bottom 2 x 140 mm fan that I'll be installing. So the case modifier of the above said at the top fan, it has to be an exhaust fan, if it draw air in, it will fight w/ the PSU fan. Is there any other choices? Because if not, then the only intake fan would be 2 x 120 mm fan at the front. Assuming we are not going to bother build a top 120 mm fan next to the PSU fan, as that would be pointless.