I wanted to make use of my Nvidia graphic card so after a little bit of reading I saw that it is possible to change it in the Additional Drivers. It's somewhat similar to here: Ubuntu 14.04 Nvidia proprietary drivers installation
Apparently it worked, at least that's what I thought in the beginning.
However, after restart, I get a black screen, although I could hear the Ubuntu login screen sound.
The thing is, I don't know how to fix it, how could I get pass that black screen to change the option to something that works?