If you see the following error in the logs

nouveau 0000:0a:00.0: firmware: failed to load nouveau/nv106_fuc084 (-2)
nouveau 0000:0a:00.0: firmware: failed to load nouveau/nv106_fuc084d (-2)

This means that you have a problem with the drivers for your Nvidia video card. To fix this error, enter in the terminal

apt update && apt upgrade
apt autoremove
apt-get remove --purge nvidia*
apt-get remove --purge "nvidia*"

Reboot with

sudo reboot

Note: To find out the name of the video driver you are using, run the command

lshw -c video | grep driver

View full information about the video card

lshw -c video

Now if you use Ububntu Install the Nvidia proprietary graphics driver and reboot

sudo ubuntu-drivers install && sudo reboot