Hi there, i just wanted to update you guys with some clocks that i found was working really good with my 8800gts 640mb. I was searching for safe clocks for it on Google, but i didn't really find any good ones, so after 5-6 hours of hard trying, and many driver crashers, i found it. Core bus: 620. Memory bus: 1020. And set your fan speed to 80-100, if you don't have good cooling. Anything over 70C (158F) would be considered bad for the GPU. Also, just to throw it in, here is safe clocks for the AMD Athlon 64 x2 4000+! Cpu frequency: 270-280, CPU multiplier 10,5, and the Voltage to 1.4250. Also again, check that the cooling is fine. Anything over 70C (158F) will be considered dangerous.