Recently Valve upgraded Proton Experimental, the special version of Proton that pulls in advancements first with support for their older CEG DRM and another new build is up. Note: you also currently need the Steam Beta Client for the initial CEG support.
In the changelog it simply notes that it improves "compatibility with games using CEG DRM" but it also has the latest fsync changes for the newer code. According to a Proton developer if you have an older Kernel fsync should be automatically disabled so if you want to use it you need to update.
Going by what we've seen, it appears that Call of Duty: Black Ops II will now load with the Campaign working but Zombies and Multiplayer remain a bit problematic with them crashing eventually. As a reminder some of these games should now see improvements on Linux with Proton Experimental:
- Aliens: Colonial Marines
- Aliens vs. Predator (2010)
- Bioshock Infinite
- Call of Duty: Black Ops
- Call of Duty: Black Ops II
- Call of Duty: Modern Warfare 2
- Call of Duty: Modern Warfare 3
- FEAR 3
- Hitman: Absolution
- Just Cause 2
- Lara Croft & the Guardian of Light
- Saints Row: The Third
- Sid Meier's Civilization V
- Sniper Elite V2
- The Typing of The Dead: Overkill
You can continue to report on CEG DRM games on the Valve GitHub Ticket.
Need to know how to actually use Proton Experimental? Here's a simple HOWTO (as it's not complicated!). Make sure it's installed by searching for it in your Steam Library, then select it from the Compatibility menu in the Properties section of a game. See our quick video below:
For an explainer in text form:
- Search for Proton Experimental and install if not already.
- Right click any game on Steam and go to Properties.
- Select the Compatibility menu on the right side.
- Ensure the "Force the use of a specific Steam Play compatibility tool" is ticked.
- From the dropdown box that appears select Proton Experimental.