I have a similar situation. I am working with Linux Ubuntu 20.04, an NVIDIA Quadro M2000M, Linux Headers 5.4.0-53-generic, and 450 drivers.
One day the card disappeared. Could not find it with lspci | hwinfo | nvidia-drivers either. I thought perhaps the motherboard had a problem. After switching nothing. However, a Dell technician loaded windows directly on the sdd and he could see the nvidia GPU. He recommended I re-install the OS. I did. Then I could see the GPU.
A few days ago the GPU disappeared once again. I began to try to explore what was going on. Uninstall drivers, reinstall different versions of them, etc. In the midst of one attempt that I cannot specifically recall, they re-appeared. Just to disappaer once again later on. I have since, not been able to get the GPU card to show up once again.
I have no clear understanding or indication of what I should do.
gpu-manager shows the following:
>> gpu-manager
last_boot_file: /var/lib/ubuntu-drivers-common/last_gfx_boot
new_boot_file: /var/lib/ubuntu-drivers-common/last_gfx_boot
can't access /run/u-d-c-nvidia-was-loaded file
can't access /opt/amdgpu-pro/bin/amdgpu-pro-px
Looking for nvidia modules in /lib/modules/5.4.0-53-generic/updates/dkms
Found nvidia module: nvidia.ko
Looking for amdgpu modules in /lib/modules/5.4.0-53-generic/updates/dkms
Is nvidia loaded? no
Was nvidia unloaded? no
Is nvidia blacklisted? yes
Is intel loaded? yes
Is radeon loaded? no
Is radeon blacklisted? no
Is amdgpu loaded? no
Is amdgpu blacklisted? no
Is amdgpu versioned? no
Is amdgpu pro stack? no
Is nouveau loaded? no
Is nouveau blacklisted? yes
Is nvidia kernel module available? yes
Is amdgpu kernel module available? no
Vendor/Device Id: 8086:191b
BusID "PCI:0@0:2:0"
Is boot vga? yes
Skipping "/dev/dri/card0", driven by "i915"
Skipping "/dev/dri/card0", driven by "i915"
Skipping "/dev/dri/card0", driven by "i915"
Found "/dev/dri/card0", driven by "i915"
output 0:
card0-eDP-1
Number of connected outputs for /dev/dri/card0: 1
Does it require offloading? yes
last cards number = 1
I couldn't open /var/lib/ubuntu-drivers-common/last_gfx_boot for writing.
Error: can't write to /var/lib/ubuntu-drivers-common/last_gfx_boot
nvidia-bug-report.log.gz (118.1 KB)