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Far Cry 5 - Consistently limited to ~42 FPS on Linux despite low GPU utilization

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ValveSoftware/Proton#9924 · opened 2026-06-30 by beermats · updated 2026-06-30 · 1 comments · github
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Bbeermats 2026-06-30 github

Far Cry 5 (552520) - Consistently limited to ~42 FPS on Linux despite low GPU utilization

Compatibility Report

Name of the game: Far Cry 5

Steam AppID: 552520

System Information

  • Distribution: Linux Mint 22.3
  • Session: X11
  • Kernel: (6.17)
  • CPU: Intel Core i5-12400F (6C / 12T)
  • GPU: NVIDIA GeForce RTX 4070
  • NVIDIA Driver: 595.71.05
  • Resolution: 2560x1440
  • Monitor Refresh Rate: 165 Hz (also tested at 60 Hz)
  • Steam: Native package (not Flatpak)
  • Game installation: Fresh download from Steam
  • Ubisoft Connect: Installed automatically by Steam/Proton

Proton Versions Tested

  • Proton-11.0-1-beta5
  • Proton Experimental
  • GE-Proton 10-34
  • GE-Proton 11-1

Both produce the exact same behavior.

Proton 9.0-4 does not launch the game on my system.


Expected Behavior

With this hardware configuration, Far Cry 5 should run well above 100 FPS at 1440p.


Actual Behavior

The game is consistently limited to approximately 40-43 FPS.

This happens:

  • during normal gameplay
  • during the built-in benchmark
  • regardless of graphics quality
  • regardless of monitor refresh rate

The frame rate is stable rather than stuttering.


Symptoms

  • FPS remain around 40-43
  • GPU utilization remains around 30%
  • Changing graphics settings from Low to Ultra has virtually no effect
  • Changing monitor refresh rate from 165 Hz to 60 Hz has no effect
  • V-Sync disabled
  • Frame time remains stable
  • The built-in benchmark reports approximately the same FPS as gameplay

The GPU never becomes fully utilized.


DXVK HUD

DXVK HUD reports:

  • DXVK 2.7.1
  • D3D11 renderer
  • NVIDIA Vulkan driver
  • GPU utilization approximately 30%
  • Very low command submission load
  • No indication of a rendering bottleneck

Troubleshooting Already Performed

Graphics settings

Tested:

  • Low
  • Medium
  • High
  • Ultra

Result:

No meaningful FPS difference.


Refresh rate

Tested:

  • 165 Hz
  • 60 Hz

Result:

No difference.


V-Sync

Disabled both in-game and through NVIDIA settings.

No change.


Different renderers

Tested:

DXVK (default)

WineD3D:

PROTON_USE_WINED3D=1 %command%

Result:

Exactly the same ~42 FPS.

This suggests the problem is not specific to DXVK or Vulkan rendering.


Proton synchronization

Tested:

PROTON_NO_FSYNC=1
PROTON_NO_ESYNC=1

No difference.


NVAPI

Tested:

PROTON_DISABLE_NVAPI=1

No difference.


Combined launch options

Tested:

PROTON_DISABLE_NVAPI=1 PROTON_NO_FSYNC=1 PROTON_NO_ESYNC=1 %command%

No change.


GPU bottleneck

Observed using:

  • DXVK HUD
  • nvidia-smi

GPU utilization stays around 30%.


Other games

Other demanding Proton titles run correctly on the same machine and fully utilize the GPU.

The problem appears to be specific to Far Cry 5.


Proton Log

A Proton log has been generated.

Notable observations:

  • DXVK initializes correctly.
  • Vulkan detects the RTX 4070 correctly.
  • WineD3D produces the same performance as DXVK.
  • No obvious fatal errors appear in the log.
  • Ubisoft Connect processes (including UplayWebCore) are started normally.

I can attach the complete steam-552520.log if requested.


Additional Notes

Because:

  • DXVK and WineD3D behave identically,
  • GPU utilization remains low,
  • graphics settings have no impact,
  • the benchmark is also limited to ~42 FPS,

it appears that the bottleneck occurs before the rendering stage.

At this point I suspect either:

  • a Proton scheduling issue,
  • a game-specific interaction with Ubisoft Connect,
  • or another compatibility issue that limits the game's main thread.

Kkisak-valve maintainer 2026-06-30 github

Hello @beermats, we're using one issue report per unofficially supported game title, and usually I'd transfer this issue report to #2356, however, you've chosen to write multiple pages of text for something that can be expressed in a couple sentences.