WE'VE WRITTEN quite a few reviews of Shuttle's cube PCs by now, yet I still can't help but marvel over these little boxes every time a new one comes along. Shuttle is obviously committed to improving its XPC line and expanding its appeal. Since the first SV24 cube appeared, Shuttle's cubes have gotten much faster, vastly quieter, arguably better looking, and—praise be!—have gained an AGP slot. Shuttle has also expanded its XPC line with versions for Pentium 4 and Athlon processors, riser cards for additional audio and video outputs, and a range of color-coordinated accessories, including a cube tote bag.

At some point, it occurred to me: these guys are bent on building a mini-PC empire.

Actually, that point was probably Computex this past year, when the Shuttle rep said to me: "We are bent on building a mini-PC empire" as he slammed his fist on a desk, scattering Shuttle trade-show schwag everywhere. Or something like that.

Anyhow, the latest building block in that empire is the fastest XPC we've seen yet, and it benefits from all the improvements Shuttle has brought to the XPC line. The SB51G is based in Intel's 845GE chipset, which is one of the fastest chipsets available for the Pentium 4, as we found in our recent review. The 845GE gives this new cube support for DDR333 memory and for Intel's soon-to-be-unleashed Hyper-Threading technology. Imagine cramming a pair of virtual CPUs into a PC the size of a toaster, and you're beginning to understand this thing's jaw-dropping potential.

So the question is: is this new XPC ready to challenge the Standard Beige Mini-Tower Case for supremacy in the enthusiast's heart? We stuffed a Radeon 9700, a half gig of Corsair memory, and a Pentium 4 2.8GHz in this box to see how it moved us. Keep reading to see what transpired.