With a locked CPU like what you have, ZeeTech, the only overclocking possible is via the BCLK. This requires a lot more finesse than overclocking an unlocked chip where you just increase the multiplier. You may be able to go as high as 4Ghz but playing with BCLK can introduce a lot of instability to the rest of the system. If you're extremely comfortable with this kind of thing and have lots of overclocking under your belt, particularly in a system where playing with the FSB was involved, you should feel right at home. Otherwise, be happy with the chip stock and that's all you're going to get.