On my A4000 desktop converted to a tower I placed a fan on the back of the case removing the hot air as well placed a fan on the side of the case located directly across from my Cyberstorm PPC blowing air in directly on it and that keeps my case nice and cool. Seen
here(you will need to drill holes in the side pannel and mount the fan to it).
The trick is to have air moving through the case from front to back constantly replacing the warm air with cooler air.
