A week after announcing the Linux-based SteamOS and promising Steam Box PCs developed by a variety of hardware partners, Valve has officially announced the specs of the 300 prototype units it will be giving out to beta testers. In a news post, the company outlined some technical details and an overall strategy for its hardware. "We wanted to accomplish some specific design goals that in the past others weren't yet tackling," the company says. "One of them was to combine high-end power with a living-room-friendly form factor. Another was to help us test living-room scenarios on a box that's as open as possible."

On that note, Steam Machine specifications vary from what would presently be considered a mid-range gaming PC to the high end of the PC gaming scale. At the lower part of the spectrum, you'll see an Intel Core i3 processor and Nvidia's mid-range GeForce GTX 660 video card, while the high end gives you a powerful fourth-generation Intel Core i7-4770 processor and the GeForce Titan, currently the highest-performing single GPU available. In between, there's the upper mid-range fourth-gen Core i5 processor and Nvidia's GTX 780 and GTX 760 — the latter is upper mid-range while the former is a high-end chip, albeit not in the same league as the Titan. All versions come with 16GB of RAM and 3GB of VRAM, as well as a hybrid drive with a 1TB HDD and 8GB of solid-state memory which should make for speedy boot times.

The whole thing is enclosed in a custom case that Valve hasn't yet revealed, but the dimensions point to a small machine: 12.4 x 12 inches and 2.9 inches tall. That's about the size of an Xbox 360 S, only slightly longer and deeper. Valve promises that the machine will be as upgradeable as possible, and it encourages people to build their own boxes with similar parts. Once the case is revealed, it will post the CAD files for its enclosure, so Steam users can make a nearly identical box.

With the exception of the Titan, these specs aren't extraordinary overkill, but they're still firmly in the "Best" category, as opposed to the cheaper "Good" or "Better" boxes that Valve has promised before. Based on current component prices, it appears that building your own Steam Machine would run between $700 to $1,800 if you followed Valve's formula here. "This design is not meant to serve the needs of all of the tens of millions of Steam users," says Valve. "It may, however, be the kind of machine that a significant percentage of Steam users would actually want to purchase — those who want plenty of performance in a high-end living room package."

Sean Hollister contributed to this report.