Short of using an ES chip, the only unlocking of multipliers is achieved through the CPU Lock Free function which allows the multiplier to be dropped from the stock to 14x. Both the processor and the mobo need to support that feature. Scroll through the list of BIOS updates for your board on the Asus website, and you'll find the list of major features for each BIOS revision. You can also check in your BIOS to see if that function is already available.