protonscr

Performance regression for every unity engine games with AMD graphics.

protonopen
ValveSoftware/Proton#8861 · opened 2025-06-28 by tails101 · updated 2025-07-08 · 3 comments · github
Ttails101 2025-06-28 github

Compatibility Report

  • Name of the game with compatibility issues: every unity engine games (tested on vrchat desktop mode)
  • Steam AppID of the game: 438100

System Information

  • GPU: rx5700xt (Navi 10)
  • Video driver version: current radv (mesa 25.1.4)
  • Kernel version: bazzite current (6.15.3)
  • Link to full system information report as Gist:
  • Proton version: latest ge (10-4ge)

I confirm:

  • [x] that I haven't found an existing compatibility report for this game.
  • [x] that I have checked whether there are updates for my system available.

Symptoms

One issue has been found here

https://community.amd.com/t5/pc-drivers-software/issues-with-amd-and-unity-games/td-p/661406

And

https://www.reddit.com/r/VRchat/comments/1lj3aw1/for_amd_users_run_vrchat_in_win8_compatibility/

In short, unity games need windows8 compatibility mode to run at expected frame rates on windows 10 and 11 with a AMD graphic card.
After testing in current bazzite, this issue affect proton as well.
I measured sometime 50% lower frame rate than expected in vrchat and other unity games with a AMD graphic card.

Reproduction

Running vrchat in proton directly show the issue
Running it in lutris with windows 8 compatibility mode fix the issue and performance are the one expected.

Fixes: i would like to have a way to select the windows compatibility version in steam game properties to apply those kind of fixes, and maybe a fix already applied in proton.
This affect games like hollow knight or the binding of Isaac or don't starve.

Kkisak-valve maintainer 2025-06-28 github

Hello @tails101, if upstream wine is affected, then it might make more sense to reproduce the performance issue with upstream wine, and report your findings to the upstream wine bug tracker.

Ttails101 2025-06-28 github

Hello @tails101, if upstream wine is affected, then it might make more sense to reproduce the performance issue with upstream wine, and report your findings to the upstream wine bug tracker.

yes but steam need a graphic change to provide more options.
wine have wine tricks.
im not sure if proton have a control panel for that

Ssjau752 2025-07-08 github

wine have wine tricks. im not sure if proton have a control panel for that

proton have protonfixes.
it is contained in GE-Proton, so you can use it from steam properties.
-pf_tricks=win8
or
mangohud %command% -pf_tricks=win8

Launch lines