MSI's BIOS of choice for most of their boards is the AMI Megatrend BIOS which has come quite a long way in terms of functionality and features, this including the option to save overclocking profiles. In order to bring up the overclocking settings you need to navigate to the Cell Menu submenu.
Adjust CPU FSB Frequency: 200 - 800 in 1MHz Increments
Adjust PCIE Frequency: 100 - 200 in 1MHz Increments
Adjust PCI Frequency: 33.3MHz, 33.6MHz, 37.2MHz, 42MHz
CPU Voltage: 1.3250v to 2.1v in 0.0125v increments
Memory Voltage: 1.5v to 2.75v in 0.05v Increments
FSB Termination Voltage: 1.2v to 1.44v in various increments
NB Voltage: 1.25v to 1.83v in various increments
SB Voltage: 1.5v to 1.83v in various increments
Overclocking of the P35 Diamond board was reasonable for the restricted voltage regulation system. We managed 551MHz out of the system, anything more than this and we found instabilities no matter how much extra Northbridge or CPU voltage we gave it. We did notice that the heatsinks on top of the voltage regulators were quite hot.
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.