Verdict: Shuttle has proven that a kick-ass gaming system can be done in miniature
If you're a fan of Shuttle XPCs, but don't want to spend £1,116, then rip these three pages from the magazine and burn them, now. Seriously, do it for your own good - I won't warn you again. And if you're not already an XPC or small form factor PC fan then prepare to be converted.
For everyone, including those XPC fans foolhardy (or rich) enough to still be reading, the news is that Shuttle's latest XPC SN26P supports SLI and is really, really good. Unfortunately, it's also really, really expensive: £466 on its own, and a whopping £1,116 with two GeForce 6800 GTs pre-installed. Ouch.
So how does Shuttle justify this disgustingly huge amount of cash? The price is partly due to the fact that you're getting a Shuttle XPC with a miniature-sized nForce4 SLI motherboard, which has two high-speed PCI-E slots; the main reason for the extra cost, though, is the customised GPU cooling system. Squeezing two high-speed 3D cards into a SFF PC is no mean feat, so, to provide adequate cooling, Shuttle has included a customised copper heatpipe cooling system that cools both cards.
The GPU cooling system is probably the most impressive aspect of the SN26P's design, particularly as Shuttle has found a way to cool two high-speed 3D cards without resorting to lots of noisy fans. Instead, the SN26P makes use of the two 60mm rear fans above the PSU. These fans are designed to cool the top portion of the chassis, which can house two additional hard disk drives, but in reality, they're fairly underused. So, to make the fans work harder, Shuttle has bolted radiators in front of them, which are attached by heatpipes to two copper GPU blocks (one for each card). This is an extremely intelligent design, because not only does it mean that each card gets its own quiet cooling system, but it also ensures that the heat generated by the GPUs is exhausted out of the rear of the chassis without creating additional heat in the rest of the chassis.
Cooling is a strong point of the SN26P all round. There are three separate channels of airflow through the system, including the GPU cooling system. The CPU is cooled by a heatpipe-assisted heatsink and two fans that draw air through the case from the right to left, a bit like a wind tunnel. Finally, the main cavity of the case is cooled by the PSU fan, which expels hot air directly out of the rear. All the fans are temperature-controlled, but the three-pronged cooling approach should mean that the overall temperature is kept in check and the fans never need to spin up.
By designing a custom cooling system, Shuttle has overcome two of the three main challenges of integrating SLI into an SFF PC: providing adequate space and effective cooling. However, when it comes to the subject of power, Shuttle seems to have missed the mark slightly.
The SN26P's 350W PSU is fairly meaty, considering the limited power output, but with an Athlon 64 X2 4200+ CPU, S-ATA II hard disk, optical drive and the two supplied Leadtek PX6800GT GeForce 6800 GT graphics cards installed, it's pushed close to the limit. After booting up the system for the first time with SLI enabled, we immediately encountered a low-power warning from the Nvidia ForceWare driver, which manages the SLI configuration of the two 3D cards.
This isn't just an idle warning, because when the ForceWare driver detects insufficient juice, it reduces the GPU clock speed from 350MHz to 200MHz, and the memory clock speed from 500MHz (1GHz effective) to just 300MHz (600MHz effective) in order to conserve power. After a little head-scratching, we decided to install Coolbits, force the cards to run at the standard clock speeds and say to hell with error messages.
As it turns out, this was the right thing to do, as Coolbits restored the 6800 GTs to their proper speeds. However, to test if the SN26P's power and cooling hardware was really up to the job, we left the system running overnight, crunching away at the Far Cry benchmark at a variety of resolutions with 4x AA and 8x AF enabled. The SN26P barely broke sweat, returning the correct performance results for each test, even after running them all seven times each. It also remained stable throughout our overclocking tests. The only bummer was that we had to force the cards to run at their correct clock speeds after each restart.
With two high-speed PCI-E slots, there's no room for additional PCI-E or PCI slots, but otherwise, the Shuttle nForce4 SLI motherboard provides everything you need. This includes 8-channel audio, courtesy of a VIA Envy24PT audio controller. This is a step above the usual AC97 audio found on most nForce4 boards, and provides good-quality sound in both music and games. There's also Gigabit Ethernet, four S-ATA II ports, and an EIDE and floppy drive port. Not all of these can be used at the same time, however, as there's only space for three 3.5in drives in the chassis - one below the optical drive (if you don't install a floppy drive) and two above it. All of the cables are provided and most are pre-routed to exactly where you need them, which makes building the system easier.
There's also a PCI-E power cable and a splitter position near the PCI-E slots, should you buy the system without graphics cards. However, you'll need to buy at least one PCI-E graphics card, because the nForce4 SLI chipset doesn't support integrated video.
PERFORMANCE
None of the SN26P's clever design elements and fancy features matter a damn if it doesn't perform, and in this respect, it didn't disappoint. If you want a small, portable PC with some serious gaming welly, then this is the box for you. The SN26P has all the application and gaming power of a full-sized nForce4 SLI system.
The only area where the SN26P fell down compared with other nForce4 systems we've seen was in the image editing test. Clearly, the SN26P wasn't able to get the most out of our S-ATA II Samsung SpinPoint P120S hard disk drive. However, it whizzed through the more CPU-intensive video encoding test, matching the score achieved by the Asus A8N-SLI Premium and even beating it in the multitasking test.
So far so good, but we really wanted to know if the SN26P could compete with a full-sized nForce4 SLI motherboard when it comes to 3D performance. Unfortunately, we can't make a direct comparison, as the only SLI results we have were taken using our old Athlon 64 3500+ test CPU. However, as our new test CPU is an Athlon 64 X2 4200+, which is basically two 3500+ cores (albeit with SSE3 and an updated memory controller), we can still make a meaningful comparison, as most games don't yet make use of two CPU cores.
Even accounting for the 3-5fps increase we'd expect from using the X2 4200+, the SN26P still compares very well with full-sized nForce4 SLI boards using two GeForce 6800 GTs. For example, the Asus A8N-SLI Deluxe managed 63.7fps at 1,280 x 1,024 with 2x AA and 2x AF, while the SN26P mustered a snappy 68.4fps. It's exactly the same story at 1,600 x 1,200 with 4x AA and 8x AF, with the A8N-SLI managing 59.3fps and the SN26P churning out 64fps, which is exactly what we'd expect.
However, one area where full-sized boards have traditionally had an advantage over SFFs is overclocking and the SN26P was a disappointing overclocker. Despite our efforts, the SN26P only managed a 210MHz FSB. This increased the CPU frequency of the Athlon 64 X2 4200+ from 2.2GHz to 2.31GHz, which resulted in a similarly meagre increase in performance. The good news is that overclocking didn't increase heat levels significantly enough to cause the fans to spin faster.
CONCLUSION
The SN26P is a masterpiece of small form factor PC engineering. The intelligent cooling system means that heat and noise are kept well under control, and it's also as fast as a full-sized nForce4 SLI system in games and applications. We even like the moody black looks, although aesthetics, as always, are a matter of taste.
The power warnings are a cause for concern, although they didn't affect performance in any way. In fact, the only really serious complaints are the lack of additional PCI-E slots for adding other components (not that any are really required), and the hideously high price tag of £466, rising to £1,116 if you want it with two GeForce 6800 GTs.
With the SN26P, Shuttle has proven that a kick-ass gaming system can be done in miniature, but we still feel that until the price falls significantly, most enthusiasts won't be tempted away from their midi-towers.
