Found this. Your mainboard may be set to 2.1v.
"go into the bios, hit ctrl+f1 at the main screen, then go to the MIT section and scroll towards the vbottom and set the voltage control to manual, then go to ddr2 overvoltage control and decrease the volts there from 2.1volts downwards in 0.1v increments until you get a better response" If it i set for 2.1, go straight for 1.8)