After all testing and data charts were completed, I attempted to unlock the dormant fourth core on the Athlon II X3 435, just so readers would know if it was successful or not. By setting the BIOS option EC Firmware Selection to Hybrid and ACC to Auto, the three-core Athlon II X3 435 booted up as an AMD Phenom II X4 B35.
All four cores were fully stable at stock voltage, so it was, of course, time to see how much this would affect the maximum overclock. While stability testing, I sought input from the other members of the SBM team, and there were no objections towards running the test suite again as an overclocked quad-core processor.
Having little time to spare, I was pleasantly surprised to find stability at 3.598 GHz without any additional voltages over the three-core overclock. The northbridge could be raised back to the same 10x multiplier, but to get the last core stable above 3.5 GHz, the HyperTransport link multiplier had to be dropped down a notch at 7x.
It’s this four-core overclock that will compete against the other two more expensive SBM machines in Thomas Soderstrom’s value comparison. But since not all processors will unlock, we’ll give readers a look at both sets of data in this article.