Looks like bad caps in PSU or motherboard. Or dirty board. And you can expect that with a cheap PSU! And I doubt it even pushes the system as hard as Prime95.
It would be most unlikely to happen due to software You could be typing in Notepad & same would happen Would you then ask if Notepad could burn mobo? sebus
Probably not if it happened with notepad. But I'm 100% unfamiliar with virtualization technology and don't know the ramifications of hardware/DMA/IO/IRQ conflicts caused by the virtual environment if not setup correctly- if that can even happen?
In my opinion using Virtual PC was just the "trigger" not the cause. In your mainboard there were some weaker components + they got even weaker after 2+ years; when you "stressed" them like this that happened... But I think the problem would of appeared sooner or later even with programs like notepad...
Your motherboard can have bricked the main tension regulators by an problem with the "Kodak FD 300 APS Film scanner" device short circuit in the cables or internally of the device.