Fixing huge FPS drops with Steam overlay in Proton games

July 19, 2019 - Reading time: ~1 minute

A current bug in WINE affecting all its forks like Proton make games have FPS drops simply by doing little circles in game with a mouse polling rate of 1000Hz (the mouse communicate information with the system every 1ms). This issue doesn't exist in native Linux games.

Another issue linked to that was Steam overlay increasing dramatically this issue after playing a Proton game and opening the Steam overlay multiple time and doing things like replying to chat or game invites, opening web browser, and so on... making the issue as bad as dropping FPS to 1 by doing little circles in Steam overlay or game..

Setting the mouse polling rate to 125Hz should 'fix' the issue in Proton games. Steps for the potential fix/workaround:

• Check that mouse request/use a 1000hz polling rate with command sudo evhz
• Modify Grub to add usbhid.mousepoll=8 to force 125hz polling rate for mouse by modifying /etc/default/grub after making sure it works according to the Arch WIKI instructions
  

  GRUB_CMDLINE_LINUX_DEFAULT="quiet splash usbhid.mousepoll=8"​