I put a new p4p800 se mobo and 2.4 prescott chip in someones xp box.Everything works perfect except the +12v line from the ps is reading 15.5v in asus probe and sandra 03.Bios (1006) reads right around 12 volts.Other than probing with a meter how do I deterime which is correct?Btw it was a clean install of xp after swapping parts.