The first step after opening the Shuttle up is taking out the drive cage by removing two cross-head screws. This cage allows for two 3.5in devices and a single 5.25in drive, and removing it gives you easy access to the RAM slots. There are four of these, and they can take a total of 8GB DDR2 memory, which can run at up to 1066MHz. On its website Shuttle has the SP45H7's memory limit at 16GB, but on the box there is a sticker stating an 8GB limit. This is likely related to users on various forums who have been reporting problems with 16GB in the SP45H7, leading to incredibly slow system performance. Then again, if you need that much memory you probably shouldn't be looking at getting an SFF PC anyway. Corsair Dominator RAM is some of the tallest memory on the market thanks to massive heatsinks, but in our test-build it fitted below the drive cage with room to spare.
Installing the processor is a bit more convoluted than usual thanks to Shuttle's proprietary Integrated Cooling Engine (with the cool acronym ICE). This consists of a copper block with heatpipes leading to a finned aluminium block that is cooled by a single 120mm fan, which at the same time extracts heat from the case. Overall it's a very clever and efficient system, both in terms of noise and space, and it kept the CPU at a maximum of 58 degrees Celsius in our warm office.
The only real niggle as far as cooling is concerned is that the motherboard chipset is actively cooled by a tiny fan, which seems like a step backward from the passive cooling on Shuttle's previous P30 series. Despite this, the SP45H7 still makes for a very quiet system, especially considering its size. Nor is its performance anything to be ashamed of. Of course we did use a budget CPU and mid-range GPU, but nevertheless our little system ran Crysis at 1,920 x 1,200 on medium detail at 35FPS average, remaining very cool all the while. Using a higher-end Quad-Core processor with an ATI Radeon 4870 (which will require a twin-molex to six-pin adapter and probably a PSU upgrade) would give you a very capable gaming machine, though when we installed a Q9770 things did get very toasty, so you might want to aim a little lower.
However, the main reason you may want to use budget components is that Shuttles command a considerable premium over standard barebones cases. Considering the SP45H7 is midrange for the XPC Prima Series, a price of around £320 does seem a little on the steep side (if this kind of money is small change to you, there's little reason not to go for the top-end SX48P2 Deluxe unless the SP45H7's slightly smaller dimensions appeal to you more). But though you could get a small Core 2-compatible system for half the price of the SP45H7, you'll be hard-pressed to find one that is quite as small or that matches the Shuttle's combination of features and build-quality.
Shuttle's well-built and feature-laden XPC Prima Series SP45H7 SFF barebones system is cool, quiet and attractive. It might be expensive, but at least you're paying a premium price for a premium product.