PC gamers who are champing at the bit to build their very own "Steam Machines" won't have to wait long to start tinkering, as Valve has revealed that its recently announced SteamOS will be available this Friday.

The announcement comes alongside word from Valve that its prototype Steam Machines, along with the companion Steam Controller, will be shipped out to 300 randomly selected US beta testers on Friday. Valve plans to notify the lucky testers via e-mail at 2pm Pacific today, and beta participants will get a special badge on their Steam accounts so journalists and fellow players can start bugging them for their impressions incessantly.

If you're not part of that lucky group of 300, though, you're probably more interested in the fact that "SteamOS will be made available when the prototype hardware ships... downloadable by individual users and commercial OEMs." More information about that release is coming soon, the company says, but Valve is already warning that "unless you’re an intrepid Linux hacker already, we’re going to recommend that you wait until later in 2014 to try it out."

This suggests the version of the OS to be released this week may require some manual compiling and building to install on an existing machine or partition. Steam controllers won't be available commercially for a while, either, so the full DIY Steam Machine experience Valve is selling is still a ways off.

In any case, Valve is promising more information on the final commercial versions of the Steam Machine program at CES in a press event slated for the evening of January 6. Ars Technica will be there, bringing you any news and announcements live as they happen.