Re: Any good advice to help me OC a Gigabyte GA-EP45-UD3PD?
Well easiest way.. (for me..)
Find a ballpark safe 24/7 Voltage that the q9550 runs at, run your voltage up to that immediately. The next step is increasing the FSB, 5-10 works safely, then stress test. When you found an OC you are happy with, or a FSB Hole somewhere, start dropping the voltage and see if your OC is still stable with the lower voltages.
With an x8.5 Multiplier you should get 3400Mhz (400FSB) to 3700Mhz (3697.5 Mhz @ 435 FSB), but mileage can vary, so just experiment with it.