About 6 months ago I built an economy Gaming PC with some OC capabilities. So using the Nvidia Core Calibration on my MSI 750-g55 I was able to unlock the 4th core and it began to identify as a Phenom II Deneb. The L3 never unlocked. In addition I was able to over clock the speed to 3.33ghz from 2.9ghz.
Recently I've began blue screening on games, so I reset to the optimal defaults. After a bit of tinkering I've been able to reunlock the 4th core and the L3 Cache showed up this time, which I'm pretty excited about. However Once I unlock the 4th core and start ramping up the MHZ I lose stability. However if I disable the 4th core I can get 3.33ghz stable again, but then I'm back down to 3 cores and no L3.
My question is which is going to yield better results in term of game performance? Should I just run the 3 cores at 3.3 or use 4 @ 2.9 with the L3?
Lastly I have one more question relative to the CPU core voltage....It would seem my mobo sets the voltage pretty low so I increased it to 1.335 after reading a few posts and specifications for the Rana vs Deneb. Is that necessary and is that the proper voltage?
As far as for vcore, at stock (1.34ish) and x3 you might get 3.4 as you have found. As an x4 I would set it to 1.35 to 1.36.
Some ballpark volts that others have found as well..
3.5Ghz - 1.4v
3.6Ghz - 1.45v
3.7Ghz - 1.5v
I'm able to operate and game unlocked at 3.6 with 1.392v, but takes 1.48v to get past prime at 3.7.
If you find it isn't stable unlocked, go back to the bios after unlocking and see if you have a "three core operation" option that will let you select cores 0,1,3 or 0,1,2. That would allow you to shut down a dysfunctional core and keep the l3 unlocked. Could also be a dysfunctional l3 that might cause problems when unlocked.