This is the First motherboard to offer GTL Reference Voltage
adjustments for Reference 0 and 1 and the reference voltage on the motherboard
chipset. GTLRef voltage is a signal voltage for the CPU FSB and is derived from
CPU VTT. This voltage actually can have a signifcant effect on the FSB your
CPU will be able to do and there is a sweet spot for the value at different
FSB range. I know from personal experience.