/etc/default/grub to reduce the resolution of default screen
sudo cp /etc/default/grub /etc/default/grub.baksudo vim /etc/default/grubvim), uncomment the lines, simply by removing the # in front of those lines.GRUB_TERMINAL=console
GRUB_GFXMODE=640x480update-grub to apply changessudo update-grubcat /etc/X11/default-display-managermdm, so then I've uninstalled all available NVIDIA drivers, stopped my display manager, installed new drivers and enabled the display manager again.sudo apt-get purge nvidia-*
sudo su
service mdm stop
chmod +x /path/to/downloaded/driver/NVIDIA-Linux-x86_64-*.run
/path/to/downloaded/driver/NVIDIA-Linux-x86_64-*.run
service mdm start
exit # logout from root userPlease remember, backup always go first! Anything you do with Linux, especially when you don't know what you're doing, create a backup copy.
TIP: for 4k monitors it's a good practice to change grub screen size, because the text on the screen is much bigger and far better visible.
If your monitor support better resolutions you can changeGRUB_GFXMODEfor another value, my highest was1024x768.
Important part of installation NVIDIA drivers is (at least for all my cases) to be logged in asrootuser, not usingsudo, but literally perform all commands of installation as root.