Had the same issue, 5900x, 3080, 32Gb 3200 RAM. ~70 fps with a lot of stutter/jitter. Seem to have alleviated the issue somewhat. run on all low to isolate, then confirm its not a VRAM issue. Closed all background apps. Nothing. Biggest fix came from using DDU to wipe my GPU drivers. Then reinstalled using NVCleanstall to get the bare minimum required software. Installed latest chipset drivers as well. Afterwards my experience was much more playable, though some maps/modes still drop me to around 80 fps, the 80 fps feels much less choppy than pre-reinstall.