jt - Prime95 the system - http://files.extremeoverclocking.com/file.php?f=103,
if when streesin the CPU it restarts or the CPU core stops testin (fails), thewn u have to up the V-core of ur CPU in the bios.
but TBO, i believe u may have a GPU that is overheating.
is ur GPU set at stock speads or is it overclocked, as this could be causin the shuttin down,
ifthis is the case, and it is set on stock speeds, then u may either have a faulty GPU, or u may need to purchase a custom cooler.
Cragsman - Intel uses the basic FSB on there systems not the Hypertransport (although they do have somethin similar on the i7).