Failed to start gdm3 after installing NVIDIA 515 driver on Ubuntu 20.04

Graphics / Linux Linux
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2

Please try creating /etc/X11/xorg.conf

Section "ServerLayout"
    Identifier  "Layout0"
    Option      "AutoAddGPU" "false"
EndSection

Section "Device"
    Identifier     "nvidia"
    Driver         "nvidia"
    BusID          "PCI:65:0:0"
    Option         "ProbeAllGpus" "False"
EndSection

I suspect the A100 get added as virtual display.