Haha, had no idea they could take so much volts! Might have a play later tonight. Was getting about 65c load (just gaming) at 3ghz, what's a safe limit for these chips?
I ran my Q6600 for over five years at 3.5ghz and 1.5v with a freezer 7. It would get over 80c when stressed but never had any problems. I only stopped using it when i upgraded to a x5460 which I now have @4.3ghz at 1.45v on the same board. The older cpus can take move voltage than the newer stuff so you should be able to push yours some more and get at least 3.2-3.4ghz without much problem.