Step 6 was just for debugging so i could see errors in case of failure.
Next step would be creating a systemd unit and a script to have this run automatically on system boot. e.g.
[Unit]
Description=Nvidia GPU initialization
Before=gpu-manager.service
[Service]
Type=oneshot
ExecStart=/usr/bin/egpu.sh
ExecStartPre=
[Install]
WantedBy=display-manager.target
Put the necessary commands into /usr/bin/egpu.sh, check if it works after boot, then re-enable sddm and reboot.
To enable the egpu for the Xserver, see:
https://forums.developer.nvidia.com/t/internal-display-freezing-on-startup-with-egpu/170468/4?u=generix
prime-select
“nvidia” aka “performance mode” means the nvidia gpu will always render everything.
“on-demand” means the nvidia gpu needs to be explicitly invoked to render an application, see:
https://download.nvidia.com/XFree86/Linux-x86_64/495.44/README/primerenderoffload.html