Valve's Steam Machines initiative will support graphics hardware from Nvidia, AMD and Intel.
In an interview with Maximum PC, Valve marketing director Doug Lombardi cleared up any confusion created by the specs released for the company's own prototype units, which are due to ship to testers ahead of a full launch next year.
The prototype specs, which were released last week, only listed Nvidia graphics cards, though Valve did state that the final versions of Steam Machines hardware would be more diverse.
"Although the graphics hardware that we've selected for the first wave of prototypes is a variety of Nvidia cards, that is not an indication that Steam Machines are Nvidia-only," Lomabrdi said.
"In 2014, there will be Steam Machines commercially available with graphics hardware made by AMD, Nvidia, and Intel. Valve has worked closely together with all three of these companies on optimising their hardware for SteamOS, and will continue to do so into the foreseeable future."
Yesterday, Valve confirmed that it will host a two-day event in January next year. Held in New York City, the event will give developers a chance to get acquainted with SteamOS, the touch-based controller and Steam Machines hardware units.