Shuttle XPC SX48P2 Deluxe

Verdict: New chipset, but not as good as its X38 predecessor.

We receive loads of mail pleading with us to review smaller-than-standard kit, and this bare bones kicks off our mission to respond to these requests. If a Shuttle based on Intel's X48 chipset isn't quite what you had in mind, go to p43 to see a micro-ATX motherboard that's a decent overclocker, or p45 to see Intel's latest tiny mini-ITX motherboard. Meanwhile, let's plough on with Shuttle's SX48P2 Deluxe.

The Intel X48 chipset inside offers two full-speed 16x PCI-E 2.0 slots, and they're arranged so that you can use either a single dual-slot graphics card or a pair of single-slot Radeon cards in CrossFire (X48 doesn't support SLI). However, the PSU installed in this Shuttle has only one 6-pin PCI-E power connector, so a CrossFire setup will probably require a trip to Maplin for a Molex adaptor. Either that or Shuttle expects you to fit a single-slot graphics card and use the second 16x PCI-E slot with a PCI-E TV tuner or sound card.

A sound card isn't an essential purchase, as the capable Realtek ALC888DD codec is built into the tiny Shuttle motherboard. Optical and coaxial S/PDIF ports can be found at the back to bypass the Realtek chip, while the four 3.5mm jacks can be used if you want to use the Realtek chip. Also at the rear are two eSATA, two LAN ports and six USB 2 ports, with a further two USB 2 ports at the front hidden behind a flip-down panel. The Shuttle also has WiFi (802.11b/g) and a fingerprint scanner.

Making SFF PCs easy to assemble is an art that Shuttle has long since mastered, and this bare bones is no exception. Assembling a PC inside it requires minimal time and effort. Dismantling the chassis reveals the same framework and cooling hardware design as that used in Shuttle's previous attempt at an overclockable SFF PC, the XPC SX38P2 Pro.

The large drive caddy can hold one optical drive, while the bay below can be used for a 3.5in external device or a hard disk. Two 3.5in caddies are suspended across the top of the case, and have small, slow-spinning exhaust fans at the rear to keep the one or two hard disks you install up there cool.

All the necessary power cables for your hardware are neatly nestled in the correct position, with the excess cable length tucked out of the way. There are four S-ATA II connectors and an EIDE port, but as there are only three S-ATA power connectors, you'll need a Molex to S-ATA power converter if you want to use three hard disks and a S-ATA optical drive.

The four memory sockets can support up to 8GB of DDR3 PC3-14440 (1,800MHz) memory. The chassis will house the oversized heatsinks used by Corsair Dominator modules, though only by the skin of a subatomic particle's tooth. The LGA775 socket will accept any LGA755 CPU, from a lowly Celeron to a mighty Core 2 Extreme. If you choose to use the latter, or another similar CPU, make sure you don't block the air vents on either side of the case toward its front, as these are for the supplied CPU cooler.

Performance

After a quick and easy build process, we were ready to test the stock-speed performance of the Shuttle. Unfortunately, we saw slower results than we'd hoped for. The Shuttle scored a measly 739 points in the image editing test, with a marginally better 995 in video encoding. The X38-based Shuttle XPC SX38P2 Pro, which is still on sale and costs £30 less than this unit, scored much higher, with scores of 957 and 1,016 in the image editing and video encoding respectively.

The X48 chipset is capable of up to 555MHz in extravagant boards such as the Foxconn Blackops and the Asus Rampage Extreme, but we were pleasantly surprised by the Shuttle's maximum FSB. The diminutive board was happy to run with its FSB at 510MHz, which is a solid result for an SSF PC and a full 30MHz more than its X38 predecessor.

With this high maximum FSB, we were excited about the overclocking potential of this Shuttle, and immediately applied our usual settings to boost our 2.66GHz Core 2 Duo E6750 to 3.66GHz. This usually only requires a vcore of 1.525V and an FSB of 458MHz. Initially, all went well, with the Shuttle producing some good scores. However, after the CPU-intensive video encoding test, the system froze halfway through the multitasking test.

While fault finding we discovered a vcore of just 1.47V in the PC Health Check screen of the BIOS, despite us setting 1.525V. This vdrop was confirmed in CPU-Z and may have been a contributed to the instability of the overclock. However, increasing the vcore to compensate for the lost voltage failed to make the overclock stable, and freezing still occurred in multitasking.

Moving our attention to other components in the system - the FSB is typically thrashed during overclocking tests, for example - we tried overvolting and tweaking everything we could, but to no avail. We were therefore forced to drop the FSB and aim at a lower overclock. The magic number for the Shuttle was a considerably slower 3.28GHz CPU, the result of an 8x multiplier and a 410MHz FSB. This overclock required us to raise the vcore to 1.5V, the Northbridge to 1.4V and the Southbridge to 1.5V. Unusually, the FSB voltage isn't shown as its complete value, but as increments of up to 150mV. For our overclock, we set the additional FSB voltage to +75mV.

The older SX38P2 Pro was capable of running our Core 2 Duo 6750 to 3.66GHz, so this X48 Shuttle would inevitably be eating its proverbial dust in the Media Benchmarks. Even with the overclock, the SX48P2 was still unable to break the 1,000-points barrier in image editing with a score of just 970 points.

The video encoding test improved by around 20 per cent to 1,201. Crysis also responded well to the new clock speed of the CPU, jumping from a 21fps minimum to a 25fps minimum.

Conclusion

When it comes to overclocking, flagship chipsets don't tend to perform as well as those they've replaced or supposedly lesser models. A significant number of world-record overclocks are from rigs based on Intel P965 chipsets, rather than X38 or X48, or even P45. The Shuttle XPC SX48P2 Deluxe is testament to this fact. Its out-of-the-box performance is below par, and its overclocking ability doesn't match that of the X38-based model that it is likely to supersede. If you're looking for a Shuttle that will overclock, snap up an XPC SX38P2 Pro as quickly as possible.