Only the Linux version includes Proton.
Optionally you can opt-in the beta program for faster access to new features.
Announced on August 21st, 2018, Proton is based on Wine and includes additional components like the wrappers DXVK (which translates Direct3D 9, 10 and 11 calls to Vulkan on-the-fly), vkd3d-proton (which translates Direct3D 12 to Vulkan), and FAudio (an XAudio reimplementation). As a rework of Steam Play, it avoids having to set up an additional Steam installation for Wine, which used to be the only way to get Windows-only Steam games working on Linux.
Proton is included in the Steam Linux client by default and Valve whitelists over 100 games known to work out-of-the-box. However, by changing a switch in Steam's settings, Proton can be enabled for all Windows games even if they don't currently work.[N 1] Proton can also be force-enabled per-game to run the Windows version of games that already have a Linux port on Steam. In addition to Steam's Linux client, Proton also comes included in Valve's own Linux distro SteamOS, which is designed for dedicated PC gaming systems, such as Valve's Steam Deck.
As of mid-2021, the only games that still don't work with Proton are mostly multiplayer games that use third-party anti-cheat systems.[N 2] However, Valve seems to be working on a solution for running third-party anticheat systems on the Steam Deck, which may be extended to other Linux distros in the future.
- ProtonDB - User reported compatibility list.
- To do this, click Steam > Settings > Steam Play > "Enable Steam Play for all titles".
- This is because anti-cheats rely on kernel functions that cannot be recreated by Wine due to the very low level of access they provide.
- Sean Hollister (September 24, 2021). One of the Steam Deck’s biggest hurdles just disappeared: EAC has come to Linux and BattlEye is inbound. The Verge.