I dont want to hijack this thread but this is how I cooled the MOSFETs in my system...
http://www.overclockers.com/tips1104/ (waterblock on the
front of the motherboard)
http://www.overclockers.com/tips1115/ (waterblock on the
back of the motherboard)
The back-side block is much more effective than the top-side block I believe since it is cooling the motherboard directly (the motherboard is used as a big heatsink for the MOSFETs).
The capacitors and other components around that area are also significantly cooler with the back-side block in place. Cool enough to be able to leave your finger tip on them indefinately. Before the blocks touching those small "donuts" resulted in instant pain.