Don’t use the .run file installer from nvidia. Use a distro package.
So run the installer with the --uninstall option first.
Then look for hints in this thread:
In short:
- update kernel (to 5.10)
- update the amdgpu firmware (you can get it from kernel/git/firmware/linux-firmware.git - Repository of firmware blobs for use with the Linux kernel directly, as they are there now)
- add the graphics drivers ppa: Proprietary GPU Drivers : “Graphics Drivers” team
- install nvidia-driver-460
- select prime profile (AFAIK Mint 20.x has its own mechanism, don’t know that exactly). The manual ways are listed here: NVIDIA Optimus - Debian Wiki