Pretty sure it isn't a cooling loop setup; have a 1600+ o/ced to 1900MHz at 2.05V and only 46-47C die temps.
BI Extreme, Innovatek wb and GPU block, Laguna 3 stauary pump (380GPH)
http://www.hagen.com/pdf/ponds/Lagun...uary_Pumps.pdf
1/2" tubing and 3/8" tubing mixed with all 1/2 barbs.