Debian 11 Nvidia 460.91.03 Dual GPU single monitor hang under load

I newly installed Debian 11 on this machine. When it is under heavy load, e.g. pandas multiproccessing, Citrix, Firefox …etc, the PC hangs intermittently. I searched the forum and found the reverse prime issue/solution for warnings in Xorg.0.log. However, creating xorg.conf, … adding “AllowEmptyInitialConfiguration” and enabling “MultiGPU” do not seem to help. I normally use both GPUs for Pytorch training and it used to work fine under Ubuntu 20.04. Please advise.
nvidia-bug-report.log.gz (1.0 MB)