Originally posted by: silveralx
im running a big water and it run's about 45C
What are your load temps? I'm assuming the V1.65 you mentioned in your first post refers to vcore? If so, than I doubt that Bigwater can handle any more than that. I'm surprised it can even handle that amount of heat. My custom H20 kit (dual heatercore, two 38mm Sanyo Denkis, D-Tek Fuzion block, and D5 pump w/ Petra top) keeps my lapped QX6700 at ~58C with 4 instances of Prime going, but that's only at 1.35-1.37V with 21-23C ambient temps. I doubt I could run 1.65V with any degree of long-term stability.
If you can do 3.6GHz with all four cores loaded than you should count yourself lucky. My bet would be you're running into temp problems. At 3.6Ghz and 1.65V you're processor is producing ~307W of energy. That is an incredible amount of heat. I'd be surprised if that Bigwater could handle much over 175W.