Id also say go with the opty 165. I have one in my rig, I have OCed to a 2.5 stable, temps never went above 49C aircooled with the stock cpu cooler, @ 1.44-1.45v. What mobo are you using? if youre not stuck to nvidia products get an ati x850xgto, awesome stats and its cheap (in the Us anyway). Just my 2 cents.