In Linux, there is two parts for the video driver, the kernel part and the X server part.
- Let's identify your hardware first. By typing
lspci | grep VGAin a terminal, you should see a line with you graphic card description (even if not configured at all).
- Let's check the correct kernel driver is loaded
find /dev -group video.
- Let's check the correct X driver is loaded
glxinfo | grep -i vendor.
If you want more help, I would like the result of following commands: (Remember, never trust command line that people ask you to execute without knowing what it does.)
lspci | grep VGA ; lsmod | grep "kms\|drm" ; find /dev -group video ; \ cat /proc/cmdline ; find /etc/modprobe.d/; cat /etc/modprobe.d/*kms* ; \ ls /etc/X11/xorg.conf ; glxinfo | grep -i "vendor\|rendering" ; \ grep LoadModule /var/log/Xorg.0.log