NVIDIA driver is not detected in Ubuntu 20.04 LTS

Solution 1:

I just had a similar situation with Nvidia driver not being recognized. Thanks to an answer to a similar complaint I did the following procedure to fresh install the Nvidia drivers:

sudo apt-get install nvidia-driver-440

Due to the number of recent posts and from my own experience, it looks like a recent update somehow deleted the Nvidia library and opened up a can of graphics woes for many of us with Nvidia adapters.

Solution 2:

NVIDIA made several mistakes on its site with drivers for 820m

Believe it or not, NVIDIA 440 does not support 820m. Geforce 820M not supported by NVIDIA since 2018 but for some reason they still post mismatched drivers on their website

Now you need to uninstall the 440 driver if possible, or reinstall your entire system.

Then try running sudo apt install nvidia-driver-390

(Yes that's right, 390 is the latest driver to support 820m)

Solution 3:

I have had the same issue, but later on I found that to update to windows 11 on my dual boot I turned on secure boot which is necessary. Then I disabled secure boot from my BIOS and everything started working again. So maybe you should try to disable secure boot from BIOS. Hope that helps!