I lowered the Cpu overclock a tad now its orking fine with no crashes but need more time to tell for sure. Because i have gone longer with no crashes before.

The thing is that this overclock worked great with crysis a much more demanding and advanced game graphics wise and my overclock passed many diffrent benchmarks 3d Mark 06, super PI, Etc my overclock was most stable, i think that game is what the problem is. I don't mind if i have to lower it slightly but i wondering if anyone else encountered this. Because this game does not even come to stress test this computer has passed on various benchmarks.

i overclocked vista also. i have been mini dumps. im running the beta so i think it might been the problem. other then that it runs alot better on the overclock profile.

If it works at stock, but not when overclocked, that typically means the overclock isn't 100% stable.

Different games and programs stress different parts of the processor. While days of stress tests are often a good indicator, they're by no means a 100% stable overclock guarantee.

I'll give you an example. Take a peak at the forums here: http://www.broadbandreports.com/forum/r21093742-Ultimate-OC-Stress-Test

I've used that stress tester in the past on a processor. It throws CPU temps quite a bit above what Prime 95 does, which obviously means it stresses a lot more of the processor, and somebody in that thread noted that a system that was Prime stable for over 8 hours failed that test in under 10 minutes.

How does this tie in to Sins? Well it may not be as simple as Sins upping the processor temp more than the other games do (heck it may not). But there could be a processor feature that isn't used in the other games that may be used in Sins may get flaky on your CPU when overclocked and/or heated up. CPU's and GPU's are nearing a billion transistors. It only takes ONE of them to act flaky at a certain speed/voltage/temp, and if a certain program uses that transistor when it's running beyond what it can handle stably, it can crash.