OK you have an opty 165 you can oc it to 250 fsb easy with out needing to volt it. The only time you need to begin to add volts is if the system starts becoming unstable at the higher clock speeds. Now how to test it is run 2 instances of prime95, one for each core, for a day or 2 you'll know if you need the volts if it crashes or comes up with errors
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