MaxWolfie
What motherboard do you have?
If it is an ASUS P5E based (X38) be very wary as those at stock overvolt the FSB Termination Voltage.
I am not sure but the datasheet suggests that the FSB Termination Voltage should be no more than 1.15Volts?
P5E3 has a minimum selectable value of....1.20V!
Likewise maximum CPU PLL is 1.55Volts
I am holding fire until ASUS resolve this issue.
BTW To achieve stability at a lower VCore, try enabling "Load Line Calibration"
John