I am now try the 10.5 multi with this QX9770. I am able to boot into windows and so far I have made it through about 30 minutes of Prime95 with 10.5 x 400MHz (4.2GHz) however, one thread quit right at the beginning and a second one quit after two minutes, the other two are still chugging away. Why is that? Not enough or too much of what?

vCore 1.44375v
MCH 1.6v
vDIMM 2.26v