When Valve announced its upcoming Steam Machine hardware last month, some eagle-eyed gamers may have been surprised to see that the official spec sheet lists support for HDMI 2.0 output, rather than the updated, higher-bandwidth HDMI 2.1 standard introduced in 2017. Now, Valve tells Ars that, while the hardware itself actually supports HDMI 2.1, the company is struggling to offer full support for that standard due to Linux drivers that are “still a work-in-progress on the software side.”
As we noted last year, the HDMI Forum (which manages the official specifications for HDMI standards) has officially blocked any open source implementation of HDMI 2.1. That means the open source AMD drivers used by SteamOS can’t fully implement certain features that are specific to the updated output standard.
“At this time an open source HDMI 2.1 implementation is not possible without running afoul of the HDMI Forum requirements,” AMD engineer Alex Deucher said at the time.