How do I fix the glxinfo BadValue error on Ubuntu 18.04?
I had a similar problem on Ubuntu 20.04, but adding the user to the video group as suggested in the other answer did not help for me.
Instead, I needed to install the correct drivers using the method described here.
-
ubuntu-drivers devicesto detect graphics card and recommended drivers -
sudo ubuntu-drivers autoinstallto install recommended drivers -
sudo apt autoremoveto remove redundant packages - reboot
-
glxgearsworked for me.
Hope that helps.