Verdict: Socket AM2 is shrunk
Shuttle virtually invented the concept of the small form factor, so it isn't surprising that the company's product range is now more numerous than the varieties of Heinz. However, while most people are still happy with the original beans in tomato sauce, hardly a month goes by without the appearance of a new Shuttle that you prefer over the previous model. Shuttle clearly doesn't want its customers to think that they have to compromise on new technology just to have a small PC.
The latest Shuttle, the SN27P2, is aimed at the new Socket AM2 Athlon 64s, while an Intel Core 2 Duo-supporting SD37P2 isn't far behind.
Like the SD31P and the SB81P, the SN27P2 is based on yet another iteration of the P-series chassis. But, as the '2' at the end of the model name implies, the front fascia is different, and you'll probably find it either cool and restrained, or a little staid, depending on your personal taste. Annoyingly, the memory card reader is absent.
Internally, it's changed too, although the layout is similar to that of the original P-series designs. The CPU is still cooled by two fans - a 70mm and a 92mm - that draw in air through a vent in the right-hand side of the case and expel it on the left side. This isn't the easiest HSF system to install, as you need a long-necked screwdriver to reach some of the screws, but it's very effective.
For more general chassis cooling, two 60mm exhaust fans are situated at the back of the case, while the PSU has its own 80mm fan. However, although all the fans are temperature-controlled to reduce noise, Shuttle has set the minimum speed of the 60mm fans at 1,600rpm, making them audible at virtually all times.
The biggest internal difference between the SD31P and the SN27P2 is in drive installation. You get the same complement of a 5.25in bay and a 3.5in bay at the front, both of which are externally accessible, plus two 3.5in bays that fill the top part of the case. However, the hard disks now sit in removable metal trays, rather than the complicated railings used in previous P-series chassis, and it's good to see that Shuttle has moved away from the confusing array of little plastic widgets it previously used. Although a tool-free design can be quicker to assemble, the P-series' version could be tricky and didn't feel secure.
Despite being an SFF, the SN27P2 has many high-end desktop features. For a start, its motherboard is based on Nvidia's nForce 570 Ultra chipset. This provides a single 16x PCI-E slot for a graphics card, plus one PCI slot for other add-in cards. The PCI-E slot is on the far right of the PCB, so we had no trouble fitting a GeForce 7900 GTX into the PC, despite the card's bulky dual-slot cooler. The SN27P2's chipset is actively cooled too, which should improve overclockability. Intel HD Audio is integrated with 7.1 surround sound, plus there's the usual FireWire routed to the front and back, and eight USB 2 ports - six at the rear and two at the front. There are four DIMM sockets, double the number usually found in SFFs. Each socket supports up to 2GB modules, so you could partner a 64-bit operating system with 8GB of RAM.
One of the four S-ATA II channels has been routed to the rear for attaching external eSATA devices. There's a clear CMOS button on the rear, although we found we didn't need to use it during overclocking, as the BIOS seemed to sense when things had gone too far and returned to default settings after a reboot. No PS/2 ports for a mouse or keyboard are provided.
There's a decent 400W PSU with twin 12Vsb rails offering 17A each, and a third 12V rail offering 10.5A. For an SFF, it's more than adequate, and should be able to power a top-of-the-range processor, a couple of hard disks and virtually any graphics card.
PERFORMANCE
We installed our usual selection of AM2 components, a 2.2GHz Socket AM2 Athlon 64 X2 4200+ backed by two 1GB sticks of fast Corsair PC2-8500 DDR2, a S-ATA II Samsung SpinPoint P120S hard disk and an Nvidia GeForce 7900 GTX.
In our 2D benchmarks, the Shuttle managed to surpass last month's Nvidia nForce 570-powered Abit KN9 SLI. The Shuttle was 4 per cent faster in the Paint Shop Pro image editing test, 7 per cent faster at TMPGEnc DVD encoding and 2 per cent faster at multitasking, making for a 4 per cent quicker overall result. Only our Need for Speed: Most Wanted gaming test was slower than the Abit desktop board, though not by much. The days when small form factors meant slow performance are clearly long gone.
The Shuttle isn't quite so stellar at overclocking, but it's still very acceptable for an SFF. Taking a cruise through the BIOS, we found that the FSB could be raised to 300MHz. The voltages are on the low side, though, with the CPU maxing out at 1.525V, and the DDR2 at 2V. Once we raised the CPU core to 1.475V from its standard 1.35V, the system was perfectly stable with a 240MHz FSB, only 20MHz behind the FSB that the overclocked Abit managed.
This turned our 2.2GHz Athlon 64 X2 into a 2.64GHz monster and, not surprisingly, the performance benefits were tasty. Our benchmark results were nearly 20 per cent faster. The only drawback was that with the CPU core voltage increased, the SN27P2's chipset fan sped up considerably, resulting in a noticeable whine. Comparing the overclocked Shuttle's results to the scores of this issue's Core 2 Duo boards doesn't make for good reading for AMD. With nearly identical clock speeds - 2.64GHz for the Athlon 64 X2, 2.66GHz for our test Core 2 Duo - the Intel systems score 1.84 overall, 14 per cent higher than the Shuttle.
CONCLUSION
Yet again, Shuttle shows its mastery of the SFF, with a well-engineered system that packs most of the features you'd want in a full-sized ATX motherboard and case into a compact, good-looking package. You pay a premium for the Shuttle name though. Nevertheless, if a no-compromise Socket AM2 Athlon 64 in a small box is your preference, the SN27P2 should be your top choice. You'll just have to live on non-brand baked beans rather than Heinz original beans to afford it.
