ok so this is my case youll notice on the side it has a rond grill and a square one above, the square one has this adjustable tube thing which you can extend up to the hsf, its directly infront of it ya see, i think its like an exhaust, well anyways i stuck a fan in in and extend it so it was a feww mm above the hsf, so it was like dual fan for the hs, but the hsf rpm went down so i geuus they must have been counteracting each other, well anyways is it ok to have a fan in that hole thing?