Phenom X3 series is a way for AMD to improve the profitability of its processor manufacturing. The quad-core processors that doesn’t make the cut for the Phenom II X4 series gets a core disabled and is instead sold as a triple-core of the Phenom II X3 series. Exactly how AMD disables the fourth core of the Phenom II X3 series is still uncertain, but what now looks like it has been confirmed is that you can actually reactivate it. Regular users can through a (VERY) simple tweak with an ACC compatible motherboard activate the fourth core by setting Advanced Clock Calibration to Auto.
This was first revealed by a Korean overclockers that managed to unlock the last core of his Phenom II X3 710 processor on a Biostar TA790GX 128M motherboard. The processor was overclocked to 3.12GHz and ran through a number of benchmarks to really check if the fourth core works and it does.
CPU-Z still identifies the processor as Phenom II X3 710, but is specified as a Phenom II X4 processor, since all four cores are active.
Since this initial reports several other users have managed to unlock their Phenom II X3 processors and according to VR-Zone, other motherboard manufacturers have confirmed that it works, among others DFI, Gigabyte and of course Biostar. There are probably more ACC compatible motherboards that will work too.
It’s not certain if it works with all Phenom II X3 processors, they talk about processors from batch 0904 and even within this batch there is no guarantee for success. Some units may simple have physically damaged cores or be unstable for other reasons when the fourth cores becomes active.
Still, it looks like an easy and very intriguing way to get some extra performance from the new Phenom II X3 processors.
