Have you seen all the SMD caps on the processor? It's ridiculous, and the 1.42 dual is a lot of heat (in comparison to single). If you put the old processor back in does it still do it? My dual 1.0 doesn't do it (super not used a lot as power supply was dead after warranty and they didn't know about recall) but my single 1.25 will do what you describe if its been used a while, or so.

I may be way off but those caps died on the motherboard on an HP I had(desktop),and since then just about everything I've worked on.