BIOS
A BIOS that we've become extremely familiar with over time. Click the right arrow and you can access the all-important frequency/voltage control settings. Not so important if you wish the run the SD31P at default settings, however.
DRAM speed can be set to DDR2-400, 533, and 667MHz. DRAM timings also see a decent degree of adjustment, and our advice would be to set them as low as you can, numerically. Timings are given a helping hand by DDR2 voltage manipulation, which tops out at 2.1V. CPU voltage can be toggled from 0.825V-1.5875V in 0.025V increments. It's handy being able to run at below-default voltages, especially in view of the comparatively limited cooling any XPC has to offer.
The CPU clock can be set from 133MHz-355MHz in 1MHz increments, too. That being the case, the SD31P supports the widest range of LGA775 CPUs around, including Extreme Editions. 266MHz FSB is a guaranteed working speed for the i945G chipset; we'll find out just how high our sample would go. The ability to lock PCI and PCI-Express buses and a chipset voltage of up to 2.1V will aid overclocking efforts.
The onboard Intel GMA950 graphics accelerator can dynamically allocate up to 128MB of system memory. Gamers, however, will definitely want to opt for a discrete PCIe card for their thrills and spills.
The BIOS allows the user to control the speed of both the CPU and 92mm exhaust fans. The CPU's, which actually controls the 92mm fan on our sample, can be set to SmartFan, Ultra-Low, Low, Mid, Full, and eXtreme modes. Full speed mode causes it to spin at almost 4,000RPM, and anything over much over 2,000RPM is instantly noticeable. System fan speed controlled the smaller, shriller 60mm fan on the CPU cooler, and it can also be set from Ultra-low to Full (no Smart Setting, though). The two rear fans spin at around 1,600RPM at all times and cannot be controlled through the BIOS. Note that DDR2 voltage is actually higher than what's inputted.
There's options for toggling the onboard features and SATA setup.
A decent enough BIOS in most respects.
