Shuttle SB81P

Bigger and badder than ever before, John Gillooly finds small form factor nirvana.

With so many small form factor models on the market nowadays it is hard to believe that it was only July 2001 when Shuttle launched its first XPC, the SV24. Since then it has continued to evolve the design of the XPC, and just when competing products were starting to catch up it has gone and raised the bar again with the SB81P.

This new model is a reaction to the increased heat and power requirements of Intel's Prescott core for the Pentium 4, with some nifty design tricks to ensure that heat does not cripple the system. This is achieved through an internal segmentation of the case design. The CPU actually sits right at the front of the chassis and ducting isolates it, allowing air to be drawn from one side of the case to the other without warming up the rest of the components. The side benefit of this is that it also makes for a quieter system; the CPU only needs one fan to suck the devilish heat of Prescott out of the box.

But the changes extend well beyond this segmentation. The case is slightly larger than previous models of XPC, but this extra space is well used indeed. It has the usual removable drive bay, which accommodates a 3.5in floppy or hard drive and a 5.25in drive.

This bay assembly also houses the card reader, which is now in its own slot, ending the era of it cannibalising a 3.25in drive bay. Plus the whole assembly now uses plastic clips for mounting, so no screws are needed in construction, and yes, that means even the drives mount using clips.

At the rear of the chassis sits a 350W power supply, as well as two extra cooling fans. 350W is a heck of a lot of power for such a small system, and is very welcome considering the spiralling power requirements of Prescott, and video cards like NVIDIA's 6800 series.

Which brings up another new feature of the SB81P. Rather than the traditional positioning of the AGP slot in the XPC, which abuts the left hand side of the case and precludes the use of dual slot graphics hardware, the SB81P has its x16 PCI Express graphics slot on the right hand side, which lets you use dual slot beasts like the GeForce 6800 Ultra and some of the more outlandishly cooled RADEON X800 cards. This XPC is based around the i915G chipset, so it has integrated graphics as well, but using them would be an insult to the latent power contained within this box.

Capping off the system, both literally and figuratively, is the inclusion of space for two SATA hard drives. These mount in removable brackets across the top of the system, and allow the SB81P to run RAIDed hard drives, which has not been feasible in the past.

With such potential in this system, we decided to load it up with some seriously power hungry hardware to see how it fared. We threw in a 3.6GHz LGA 775 Pentium 4 CPU, two SATA hard drives, DVD burner, RAM and a PCI Express GeForce 6800 GT card. One shortcoming we did find was that the limited number of power cables meant we needed to daisychain power adapters in order to get the required six pin power connector attached to the video card.

Once attached it worked fine, but it was both annoying and added an extra tangle of cables to the otherwise clean layout of the box.

Once we had the 3D stress tests running on the SB81P, the other worry we had emerged. While the ducting system is great for removing the heat of the CPU from the system, it does mean care needs to be taken to keep the sides of the SB81P clear of obstructions.

To see how it fared we blocked off the vents with some boxes and waited.

After about 20 minutes we started to hear the fan spooling up to cope with the heat buildup, and about 10 minutes after that the system crashed.

The exhaust side of the case was scalding to the touch after this, but after half an hour or so of cooling down we rebooted the system and it was fine.

Overheating will cause the Pentium 4 to throttle back speed, so fan speeds may need to be adjusted in the BIOS.

Having the hard drives just under the top cover of the case also means that this heats up as well, although not to any dangerous degree. But care must be taken with placement of the SB81P so that the air can be properly expelled.

Yet again Shuttle has raised the bar with the SB81P. Rather than just build a system to cope with Prescott, it has gone back to the drawing board and improved nearly every aspect of its already stellar design. Not only does the box contain room for a suite of bleeding edge hardware, the 350W PSU makes sure that it will run smoothly. As long as you are conscious of the need for ventilation around the chassis, this is a damn nice solution, and if Intel's CPU ran cooler it could well be classed as small form factor perfection.