While I'm not totally sold that Valve's second attempt at bringing the Steam Machine to life will find a broad audience, I think the pint-sized PC looks very cool (the fact that it resembles an Xbox Series X cut in half is downright hilarious).

While the Steam Machine's technical specs, including its AMD Zen 4 CPU, AMD RDNA 3 GPU, and 16GB DDR5 RAM make it a reasonably powerful PC, one key port spec stood out to me. On paper, the SteamOS-powered PC is only listed as supporting HDMI 2.0, which makes it seem like it can only handle 4K/60Hz refresh rate when using the port. For a modern gaming device, this stands out as odd, even if Valve's performance target is 4K/60Hz for the Steam Machine. Yet Valve's own website lists the Steam Machine as supporting 4K/120hz, HDR, FreeSync, and CEC compatible. Confusing, right?

Steam Machine.
Valve
4K Capability
Yes
Brand
Valve
Game support
Steam
Storage
512GB, 2TB
CPU
Semi-custom AMD Zen 4 6C/12T, up to 4.8GHz
Connectivity
Wi-Fi 6E, Gigabit Ethernet

RAM
16GB

The Steam Machine does mostly support HDMI 2.1

Valve should probably make this clearer at some point

After researching in the depths of Reddit threads and checking out Linus Tech Tips' and Digital Foundry's latest video, two YouTube channels that went hands-on with the Steam Machine, it's clear the device's hardware is actually HDMI 2.1 compatible, which means it's capable of handling 4K/120hz. The only reason the Steam Machine's specs list HDMI 2.0 is because the HDMI Forum won't officially allow HDMI 2.1 support on Linux devices.

While not many games will actually run on the Steam Machine at 4K/120hz given its hardware power, it's likely that some less resource-intensive indie titles will be able to handle the higher resolution and refresh rate. Add in the fact that Valve wants owners to be able to easily use the Steam Machine in their living room hooked up to a TV, and HDMI 2.1 becomes that much more important since it's the port technology most modern televisions feature, alongside DisplayPort 1.4 for higher resolutions and refresh rates on monitors. However, there's no DSC compression support on the Steam Machine's HDMI 2.0 port, at least not at launch, so the maximum resolution and refresh rate you'll be able to get from it is 4K/120Hz.