The first of what will probably be many, Piston is a unique version of Xi3's modular X7A PCs and what exactly is in it is anybody's guess. Xi3 does have a 7 Series PC that's "somewhat" (their words) aimed at gaming, but to say they were "cagey" about whether or not its specs are anything like the upcoming Steam Box's would be a massive understatement.
That said, Xi3's gameriest modular computer boasts a quad-core 64-bit x86-based processor, up to 8GB of DDR3 RAM, an SSD as large as a terabyte, supports up to three displays and resolutions of up to 4096x2160. Then, of course, there's the PC's modular aspect; its motherboard is split into three distinct pieces, arranged into a cube to make the whole device small enough to fit in one hand. Each one can be swapped out for a better one as time goes on, to keep up with whatever innovations are coming down the pipe. All that can be yours for $999.
And while that's the best guess for what the Piston could be, nothing is certain, and there's no telling what other kind of Steam Boxes could be bubbling up in the shadows. Valve has made it explicitly clear that this partnership with Xi3 is not not not monogamous, and just because these two are mackin' right now, it doesn't mean their love-child will keep Valve from courting some other prospective mates. Even though Piston's in its infancy—a spokesman at Valve off-handedly commented the model they have on display doesn't even do anything yet—it's the pretty little leader of an interesting charge.
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