http://www.hardwarecanucks.com/forum/troubleshooting/44595-wont-boot-just-installed-another-cpu.html
Is this somewhat related?
Is this somewhat related?
If I think I have this right:
1. memtest turns up nothing
2. computer crashes with XP, and also with Ubuntu (are you able to recreate this? Or was the Ubuntu crash a fluke?)
3. in Ubuntu, crash occurs when watching videos???
Crashing with two different OSes tells me its hardware, and not software. You have already ruled out ram it seems. If you get crashes in Ubuntu and Windows, and the issue happens more often when watching videos, I would think its your video card, or possibly the psu.
So again, if you have the problems with two different OSes then I would next see if you could swap the GPU first, and then the PSU if the problem persists.
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