Hello nehachandra
It sounds like heat is the issue to me too.
I have also noticed that ANY dynamic BIOS tuner, nTune or ESA Tools, cause MAJOR problems with the system.
Since you have stated that you recently built this machine, and I noticed that you have nForce and gForce hardware installed, I can only assume that you installed the software that came with them; nTune/ESA Tools.
Try uninstalling them if you have them installed.... This has solved several issues I had when I first built my machine...
Sven2157
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Sven2157
Sometimes I think that people seriously lack imagination... Then I receive another Tech Support call!