To start with, just raise the multi one click at a time and test for stability while watching temps don't get too high. Be sure to turn off turbo mode. If all is good, Repeat. Eventually you will have an unstable result in prime95, Intel Burn Test, or what ever you use. You can either back off and live with that, or start raising the vcore a tiny bit at a time to make it stable again. Then you can probably get a bit more from the multi too. You can make it more complex if you want to squeeze every last drop of clock speed out of the CPU. But that would take a long discussion. Look to the google machine for greater depth.