[2020] GPU usage drop after ~1hour gameplay

Interesting.

Could you post your system information? You can upload it using the button. This would be easier to reproduce if we knew whether you had an Nvidia or AMD video card, which driver you’re using, which Operating System (e.g.Win10, Ubuntu 20.04) you’re using, and so on.

Is there a corresponding change in temperature when the utilization & FPS begin to drop?