Compatibility Report

• Name of the game with compatibility issues: Hogwarts Legacy
• Steam AppID of the game: 990080

System Information

• GPU: RTX 5070
• Video driver version: 580.142
• Kernel version: 6.19
• Proton version: Proton Experimental (Proton 11)
• System Information: https://gist.github.com/CerealKilla123/9dbdceb169338c37384ed6e6f12f6f3f

Symptoms

Previously game was running perfectly fine and actually smoother than on windows (where I frequently had FPS spikes). Since updating to Proton Experimental a couple of hours ago, FPS spikes are very frequent when casting spells or dodging or just taking any action in game. I tried recompiling the shaders, restarting my system and making sure nothing else was running in the background and the game was still consistently stuttering a couple of times a minute which made gameplay very frustrating.

Confirmed with MangoHUD that game was using NTSync. Tried with "PROTON_NO_NTSYNC=1" Environment variable and game was back to running perfectly fine as it was before.

Reproduction

Benchmark/play game with and without "PROTON_NO_NTSYNC=1" and compare performance. FPS spikes and frame-times of 60ms+ are very frequent with NTSync.