BIOS options
Although their limited cooling generally keeps small form factor systems away from serious overclockers, that hasn't stopped Shuttle from equipping the SG33G5's BIOS with a handful of options for those looking to turn up the clocks.

There is only a handful of options, though. For example, the BIOS lacks control over the Core 2 multiplier, and memory speed options are limited to 667 and 800MHz. Front-side bus speeds are available all the way up to 600MHz, though, and processor voltage can be increased by up to half a volt. You can also push the memory voltage as high as 2.575V and tweak voltages for the front-side bus and chipset components. Pay particular attention to that memory voltage setting; we had to give our Corsair DIMMs a little extra juice to get them stable with 4-4-4-12 timings at 800MHz on the SG33G5.

For those seeking more simplistic overclocking controls, the BIOS also offers the ability to overclock the system automatically by between 3% and 20% under load. The value of load-based dynamic overclocking seems a little questionable with the Core 2 Duo's C1E Enhanced Halt State and SpeedStep throttling clock speeds at idle, though.

Delving deeper into the SG33G5's BIOS reveals all the memory timing options you'd expect. Limited control over the integrated GMA 3100 graphics is also included, allowing users to decide how much video memory to provide the IGP and whether that memory is allocated in one chunk or doled out as needed.

Perhaps the most important element of the SG33G5's BIOS is its fan speed control section, where users can choose between five fan speed options. Having five such options is great, but we'd much rather be able to define actual temperature targets and the speed at which the fan ramps RPMs as things heat up.

Shuttle has actually moved more fine-grained fan speed controls from the BIOS to its XPC Tools software for Windows. However, the current version of XPC Tools doesn't work with Vista x64, leaving our test system out in the cold. Shuttle is aware of the issue and has plans to port XPC Tools to 64 bits, but there's no timeline for an x64-compatible release.