I have not overclocked in the BIOS since the good old Celeron 300A days, but I seam to be having trouble locating a "Soft FSB" type tool that will allow me to adjust the CPU clock speeds on my Intel C2D T7700.
You might give a try to clockgen, but their official site isn't up at the moment, so you'd have to google for a download. I don't know if your motherboard or chipset will be supported, but it is worth a try.