Following on Steam's unveiling of SteamOS and its associated Steam Controller last week, Xi3 has started taking pre-orders for the Piston, its PC-meets-console box that the company first unveiled at CES in January.

The $999 system, which will be available on November 29, measures about four inches on each side. It's a noticeably smaller form factor than most gaming PCs. The core specs haven't changed much at all since the system was first announced: an x86-based AMD 3.2Ghz quad-core chip with 384 "programmable discrete-class graphics cores"; 8GB of RAM and 128GB of solid-state storage; 12 USB ports; and support for up to three monitors (mini-DP, HDMI and DisplayPort) at up to 4K resolution.

Those specs should provide decent-if-not-stellar performance for today's high-end PC titles, but the Piston delivers it at a price that's either much lower than a tricked-out gaming rig or much higher than a next-generation living-room console (depending on how you look at it). For its part, Xi3 seems to be positioning the system as a living-room console replacement. The company justifies the higher-than-console price by pointing out that the Piston "offers users a level of freedom and choice unheard of in the gaming console world," including the ability to do more than just play games.

Xi3 is also touting the Piston's upgradeability through a somewhat unorthodox PC architecture. The system "replaces the typical single motherboard found in most computers with three miniaturized and interconnected boards," according to the company. It plans to release its own upgraded boards and components so that these boards can be replaced individually as PC technology improves.

While Xi3 said it has "received an investment from Valve," the nature of the relationship between the hardware-maker and the SteamOS-maker is decidedly fuzzy. In any case, Xi3 is being careful not to refer to the system as a "Steam Box," even though it will obviously support Steam games through Windows or Linux. Xi3 seems confident that the box will be able to run the newly announced SteamOS. The company said, "we’ll have to wait until SteamOS is available to confirm this" and to work out whether the OS will be pre-loaded on the system.

Xi3 took limited pre-orders for the Piston at the SXSW gathering earlier this year; the company has opened it up to wider orders today.