Valve isn't ditching Windows or x86, but it's quietly making both optional
… The Steam Machine ships on x86; the Steam Frame VR headset uses Qualcomm's Snapdragon 8 Gen 3, an Arm64 mobile SoC, which means SteamOS and its surrounding compatibility stack span both x86 and Arm. The Steam Machine store page is live with full specs, but still hasn't been officially announced. …