400w Sparkle International PSU (Antec TruPower level)
I've got plenty of cooling. That's a 50cfm fan on my SLK800-A, which hangs out over the sides just a bit on the top and bottom, moving air over the heatsink of my northbridge and all of the motherboard in that area. I've also got a fan where my highest two 5.25" bays are, blowing air across those hard drives in the upper left. Then, for the two hard drives below that screwed into the side of the 5.25" bays, I've got the fan from the stock AMD supplied heatsink/fan combo running right in front of those drives. For those bottom hard drives in the aluminum rack (which helps dissipate heat by itself) I've got another 60mm fan in the front blowing air over them.
Also, I have an 8" desk fan blowing air in the vicinity of my PCI cards and CPU, removing hot air from the cards and whisking the hotter "used" air from my CPU away.
It hosted the server once upon a time... but long before it was ever THIS good.