External appearance
Those familiar with Shuttle's fifth-generation P-series design (including SB95P v2, and SB81P) will undoubtedly see the family resemblance immediately. The cool, understated finish is helped by Shuttle covering front-mounted ports and sockets, and the front has a black plastic surround that's split into 5 sections. The SD31P measures in at 325mm (l) x 220mm (w) x 210mm (h). As mentioned, that makes it one of the larger XPCs currently available. Shuttle also continues to use a USB 2.0-driven 8-in-1 card reader, situated at the very top, and it supports all the usual formats, including Compact Flash, Smart Media, Secure Digital, Multi Media cards, Memory Stick, and Memory Stick Pro.
Right below is a 5.25" bay that is, obviously, suited to an optical drive. Below that, and accessed by pressing on the right-hand side of the flap, is space for a 3.5" drive. Power and reset buttons then break up the grey-ish monotony, and Shuttle includes a small LED that indicates hard-drive operation. Incidentally, the power button has a blue ring around it whose brightness can be manipulated from within BIOS. Right below the reset button is where you'll find the various front-mounted ports.
Microphone and headphone sockets sit to the right of a couple of USB 2.0 ports and a single FireWire400.
You can see how easily the brushed aluminium sides pick up fingerprints. With the aid of internal cooling, the vent on the right-hand side draws in cool air which is expelled through a matching vent on the other side.
Being powered by an i945G motherboard, the two slots on the left-hand side are for a x1 slot (right) and x16 slot that's suitable for running a discrete PCIe-based video card.
The middle section is dominated by fans. The upper grilles have a couple of 60mm fans behind them, blowing hot air from out of the chassis. Having an external clear CMOS button is an excellent idea for SFF PCs, and Shuttle duly obliges with one next to the left-hand grille. A FireWire400 port can also be seen to the right, and further right is the hole where the Shuttle wireless module's antenna, when bought separately, would fit into. The lower 80mm fan exhausts the hot air produced by Shuttle's 350W PSU.
A closer look at the gaggle of ports highlights some interesting features. Onboard video is accessed by plugging in your monitor via an HD15 connection. PS/2 ports are also regular fare. The RJ45 socket is the interface for the SD31P's Gigabit Ethernet, and it's surrounded by 4 USB 2.0 ports. However, take a closer look at what's right underneath the second batch of ports. It's a single SATA port that supports hot-plugging, making SATA act and behave just as well as USB 2.0. Of course, you'll need a SATA drive with its own power source since no meaningful power can be drawn through the rear-mounted port on the SD31P. S/PDIF optical input and output and a coaxial output make the most of the SD31P's audio ability, which, as you will see when we take a look inside, is rather good. On a wish-list note, we'd liked to have seen Shuttle make space for a DVI connector on the rear.
Clean lines, a decent arrangement of ports and sockets, and a minimalist look makes the SD31P one of the better XPCs out there. Let's see if the internals can match the externals.
