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One curiosity in the Steam Machine specifications is its HDMI output, which is labelled as "HDMI 2.0" despite the fact that the Machine supports a lot of HDMI 2.1 features. The reason is down to HDMI 2.1 support on AMD graphics cards in Linux, which SteamOS is based on. In short, Valve needed to work with AMD to shore up Linux support for the display standard, but that work is now complete. Here's Valve SteamOS architect Pierre-Loup Griffais:
"We've worked a ton with various partners in AMD, who has done a ton of work to try and drive resolution there, and we think that's fully resolved. The current software stack we have on Steam Machine has HDMI 2.1 VRR enabled, not only on FreeSync displays but also on HDMI Forum VRR ones. This is a very important part of the performance puzzle, along with the FSR 4 boosts to come."
Griffais went on to say that while 4K 120Hz is the current limit over HDMI, relying on compression, 4K 144Hz uncompressed and 4K 240Hz with Display Stream Compression will also be possible over HDMI 2.1 FRL with a forthcoming update, so stay tuned for that.
It's worth noting that the Steam Machine also has a DisplayPort 1.4 output, which already supports 4K 144Hz or 4K 240Hz with DSC.
I've got one of those 4K 240Hz monitors as my main display, so I'm curious to see how long it will take for that FRL patch to reach SteamOS - even if native 1440p is the more natural output resolution than 4K is, it's nice to see the full resolution and refresh rate when you're in the interface!
What do you make of the news? Do you need this update, or is your display within the 4K 120Hz bounds? Let me know in the comments below.