Now, to the BIOS. ASUS uses its trademark Award Tab BIOS as we like to refer to it as. Its appearance and colour scheme is identical to the reference BIOS Intel uses for its own desktop boards, but ASUS has a lot more tweaking options under its hood.
The AI Tweaker tab has all the overclocking options, apart from actual control of the CPU ratio. This has to be done in the advanced tab under the CPU Control Sub menu. Also from here, you can set the boot-up VID rather than having to rely on the default VID the CPU is set for.
FSB Frequency: 400 - 800 in 1MHz Increments
PCIE Frequency: 100 - 180MHz in 1MHz Increments
CPU Voltage: 0.85v to 2.1v in 0.00625v increments
CPU PLL Voltage: 1.5v to 2.78v in 0.02v increments
FSB Termination Voltage: 1.1v to 1.9v in 0.02v increments
DRAM Voltage: 1.8v to 3.0v in 0.02v increments
NB Voltage: 1.1v to 20.6v in 0.02v Increments
SB Voltage: 1.1 to 1.4v in 0.1v increments
SATA PCIE Voltage: 1.5v to 1.8v in 0.1v increments
Ratio and Dividers
CPU GLT Reference (0/2): 0.370x to 0.760x in 0.005x increments
CPU GLT Reference (1/3): 0.410x to 0.800x in 0.005x increments
FSB Strap to NB: 200-266-333-400
Overclocking the ASUS P5Q Deluxe was a dream. With all the options onboard, we managed to hit a max FSB of 564MHz, which is quite high for a DDR2 supporting motherboard. A very impressive result here.
For this result, we had to adjust the GTL reference multipliers and the DDR2 channel ref voltages.
Important Editor Note: Our maximum overclocking result is the best result we managed in our limited time of testing the motherboard. Due to time constraints we weren't able to tweak the motherboard to the absolute maximum and find the highest possible FSB, as this could take days to find properly. We do however spend at least a few hours overclocking every motherboard to try and find the highest possible overclock in that time frame. You may or may not be able to overclock higher if you spend more time tweaking, or as new BIOS updates are released. "Burn-in" time might also come into play if you believe in that.