The reference board for SiS 672FX allowed us to overclock our CPU, increasing its external clock rate in 1 MHz steps.
On this board we could set the external clock rate at 313 MHz with stability. With this overclocking our Core 2 Duo E6700 which normally runs at 2.66 GHz was running internally at 3.13 GHz, a 18% increase over its standard clock rate. Not bad at all for a motherboard with on-board video.
With this overclocking the performance measured by PCMark05 increased 9.66% but we saw no performance increase on Quake III.
Keep in mind that we could set a higher clock rate but the system wasn’t stable. We only consider an overclocking to be successful after we could run PCMark05 and Quake III at least four times with no crashes.