if you want help you should tell us which motherboard you are using so we can see if that might be the issue, and how are your tempratures and voltages when running it at 4.2 ghz. also what cooler are you using?
bump i really need help with this as their is not much well known guides with my motherboards bios i will be upgrading in october and will have about 400$ in cash to spend on a mobo and cpu.