You've got a couple problems trying to OC with this board. First, it doesn't 'unlock' processors like nForce2 does. So without mod'ing the CPU you can only OC by increasing the FSB. The next problem is that there's no 1:5 PCI divider, which means you probably won't be able to increase the FSB too far beyond 133MHz. As someone mentioned, the "333" only refers to 166MHz memory (DDR, hence the 2 X 166 = 333), only 166MHz FSB is not 'officially' supported. However, you can adjust the FSB in the BIOS. Check the manual, and it will tell you where the CPU settings are. You have to change the CPU setting from 'Auto' to 'Manual' and then you will be able to adjust some of the CPU settings, but not the multiplier.