I do not really have a body for this. I was not aware that this is a thing and still feel like this is bs, but maybe there is an actual explanation for HDMI Forum's decision that I am missing.

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At this time an open source HDMI 2.1 implementation is not possible without running afoul of the HDMI Forum requirements.

 

At this time an open source HDMI 2.1 implementation is not possible without running afoul of the HDMI Forum requirements.

 

The HDMI Forum, responsible for the HDMI specification, continues to stonewall open source. Valve's Steam Machine theoretically supports HDMI 2.1, but the mini-PC is software-limited to HDMI 2.0. As a result, more than 60 frames per second at 4K resolution are only possible with limitations.