If you have a NVidia graphics card, you will need to install drivers for your Linux Mint OS to use this hardware. If you got it, use it, especially if you are using multiple screens.
Follow the instructions on this website: http://www.binarytides.com/install-nvidia-drivers-linux-mint-16/
Do not install drivers from the NVidia website. The website above is simple and less manual steps. Do it.
Download your driver from the NVidia website. It will be large .run file. Hold
CTRL + ALT + F1to enter into an a full screen terminal. Log in with your username.
Stop your x server:
sudo service mdm stop
sudo add-apt-repository ppa:ubuntu-x-swat/x-updates
Refresh your available sources:
sudo apt-get update
Install their NVidia-current, which is outdated but sets up many things to avoid errors with installing on your own:
sudo apt-get install nvidia-current
Do Steps 2 and 3 again to get into the full screen terminal. Run your NVIDIA*.run file:
Follow prompts. Restart:
If Cinnamon crashes, you will need to read this and figure out what is best for you.