Ubuntu by default installs graphics drivers automatically and configures the best graphics resolution. If you have purchased new graphics card, chances are the drivers need to be installed manually. Here is what you need to do.
1. Go download the linux drivers from nvidia website. Download the .RUN file which is about 60mb.
2. First, open the downloaded file, right click and mark it as execute.
3. The drivers can only be installed in command mode, under sudo and the graphics daemon must not be running. Switch to command mode tty CTRL+ALT+F1, then run this command to stop the display manager
sudo service lightdm stop
If you see a blank screen, that means the mode resolution conflicts with improper video driver. Never mind fix that by running this..
sudo sed -i -e 's/#GRUB_TERMINAL/GRUB_TERMINAL/g' /etc/default/grub sudo update-grub
4. Run your nvidia installer
sudo ./NVIDIA_750TI_350.linux64.run
5. Thats it, once down restart your x-server
sudo service lightdm start
You will see new graphics set to optimal resolution!!
