You had problems with heat in the case!!
I'll build a Silent Gaming PC for a friend, and I'll mount an extra CPU block with an CPU Fan cooler circulating the air inside the case, and placing it first in the cooling flow. I'll use a Nexus Brezzer 500 case.

I hope my friend buy's this PC, then I'll get back to you with the results, might be that it doesn't do any good!!

/Bektor