Re: un expected shutdowns
I am in the exact same boat as you, and have ruled out everything hardware except the mobo. It seems to be software, so I am upgrading to windows 7 to see if it works.
Are your crashes totally random or is there some pattern to them? For me, it is heavy gpu usage. Keep track of when it happens if you are not already, and we may be able to figure this out.
Also, post up CPU and gpu temps. That could easily be the culprit.
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