Moving into the BIOS; MSI uses American Megatrends BIOS which they have used on just about all of their boards for the last five years. AMI's BIOS has picked up so far that it's no different in setup to Awards ver6 BIOS. As usual, MSI has its overclocking settings under the Cell Menu.
FSB Clock: 400 - 2500 in 1MHz Increments
DRAM Clock: 400 - 1400 in 1MHz Increments
Adjust PCI-E Clock: 100Mhz to 200MHz in 1MHz increments
MCP PCI-E Clock: 100Mhz to 200MHz in 1Mhz increments
CPU Voltage: +0.01250v to +0.3875v in 0.01250v increments
DRAM Voltage: 1.5v to 2.5v in 0.05v Increments
SB Voltage: 1.5v to 2.0v in 0.05v Increments
NB Voltage: 1.2v to 1.6v in 0.05v Increments
PCI Expander PLL Voltage: -63 to 80 in Various Increments
DIMM reference Voltage: -63 to 80 in Various Increments
Memory Terminator Voltage: -63 to 80 in Various Increments
CPU GTL Reference Voltage: -63 to 80 in Various Increments
NB GTL Reference Voltage: -63 to 80 in Various Increments
FSB Termination Voltage: -80 to 63 in Various Increments
SB Sleep Mode: -63 to 80 in Various Increments
With all the overclocking options in the BIOS, we managed to hit a healthy 561MHz FSB, which is slightly faster than the ZOTAC board, but we again had to tweak all the voltages since the 790i SLI is a very power hungry unit and generates quite a bit of heat.
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.