I built my PC near the end of 2024, originally using a Radeon 6750 XT. I later upgraded to an RTX 5070 and then to an RTX 5080 in March. After each hardware upgrade, I completely reinstalled Windows and the graphics drivers.
American Truck Simulator used to average around 100 FPS without mods, about 80 FPS with mods on the 6750 XT, over 120 FPS with the 5070, and more than 150 FPS with the 5080 while using mods and graphics add-ons. Over the past few weeks, though, performance has suddenly fallen to roughly 30 FPS with severe stuttering and occasional crashes. Other games have also become much less playable; Resident Evil: Requiem struggles above low settings.
GPU usage is usually around 80–90% and CPU usage is around 50–70%. Neither component goes above roughly 72°C, and I have not noticed anything unusual consuming RAM or VRAM. My graphics drivers are current, and I normally shut the PC down when I am finished using it. Most of my files are backed up, so reinstalling Windows would be manageable, but I would prefer to troubleshoot first. What should I check before doing a clean Windows installation?
2 Answers
A Windows reinstall probably should not be the first step. A performance drop from 150 FPS to 30 FPS usually points to something measurable, such as reduced GPU clock or power draw, a background process, a driver issue, a game setting change, or a problem with the installation. Monitor GPU clocks, power usage, temperatures, CPU and GPU utilization, RAM and VRAM use, and frametime while the game is running. Also check Reliability Monitor and Event Viewer for errors that line up with the crashes.
Before reinstalling, check the basics that can cause a sudden performance limit: Windows power mode, NVIDIA Control Panel power settings, GPU temperature and hotspot temperature, CPU temperatures, available storage space, and whether the card is reaching normal boost clocks. Check the SSD's health as well. If all of those look normal, try verifying the affected games and testing with a clean driver installation. A fresh Windows install is reasonable as a last resort, but it may not fix a hardware, power, or driver problem.
The overlay shows that temperatures and utilization look similar to when the system was performing normally. I have not yet compared the clock speeds and power draw closely, so I will check those next.