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Now that the Steam Machine has begun to reach customers, Valve has released official Windows 11 drivers for the PC via the Steam Support site. Right now, that includes four components: a graphics driver, a Wi-Fi driver, a Bluetooth driver and an SD card reader driver; all other components ought to work out of the box with the default Windows driver library, and the OS should install just fine with default drivers.
Installing Windows takes away one of the biggest advantages of the Steam Machine - SteamOS - but does allow for certain Windows-only games and applications to be played without the need for a translation layer, including Game Pass games via the Xbox app.
The big limitation right now is that dual-boot support is not yet available, despite Valve noting that "Steam Machine [is] fully capable of dual-boot". Instead, the issue is that the SteamOS installer doesn't yet include a dual-boot wizard, though this is planned. Once complete, this "will ship alongside SteamOS".
This could allow the single SSD found in the Steam Machine to be split into multiple partitions (hopefully you got the 2TB model!) or potentially for one OS to be installed onto an SD card (something that is already possible for Steam Deck and PCs, but not particularly desirable if performance is the goal).
Valve does state that, while "other applications and OSes can be installed", the Windows drivers are provided as-is, and they won't provide support for Windows on Steam Machine, and customers should follow recovery instructions if they need to restore the default SteamOS image.
To enter the boot menu to use your Windows 11 installation media (eg USB drive), you'll need to turn off the Steam Machine, then tap the escape key repeatedly after turning the Steam Machine back on. Valve note that entering a Windows product key requires internet access, so I'd suggest skipping that step or using a wired ethernet connection until you have the option to install the Wi-Fi driver linked on the support site. You could copy the drivers to your install USB after making it to speed up that process, of course.
I personally don't plan to use my Steam Machine to play any competitive games with anti-cheat, so I'll probably keep it on SteamOS for the foreseeable future - but dual-booting might be a fun option down the line, potentially as a way to make better use of my Game Pass subscription for party games and the like.
What use-cases do you see for Windows support on Steam Machine? Do you think you'll use this capability, or is it more of a gesture than anything else? Let me know in the comments below.