Both boards use an identical BIOS layout which resembles the ASUS BIOS menu used on their current generation. All of the features for overclocking are under the Advanced main tab. From there you have to go to three different menus to find the settings. Both boards have identical settings.
CPU Frequency: 100MHz - 800MHz in 1MHz Increments
PCI Express: 50MHz to 150MHz in 1MHz Increments
CPU Voltage: 0.81875v to 1.60v in various increments
DRAM(DDR3): 1.47v to 2.375v in various increments
NB Core: Auto, Low, Middle, High, Highest
SB Core: Auto, Low, Middle, High, Highest
SB 1.1v: Auto, Low, Middle, High, Highest
VTT Voltage: Auto, Low, Middle, High, Highest
GLTREF Voltage: x0.615, x0.63, x0.65, x0.67
PLL Voltage: Auto, Low, Middle, High, Highest
With both boards having the exact same settings, we expected to see a similar result in the FSB department and we weren't wrong. We managed a total of 507MHz out of the P43 and just a little higher of 512MHz out of the P45 board; very impressive results here.
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.