So, I'm kind of new to Ubuntu and Linux in general, I installed the latest (Ubuntu 14.04) and everything went fine, except for the resolution so I thought that it was a driver problem because I have a AMD HD 7750 and maybe it required additional proprietary drivers so I installed AMD Catalyst (Latest version), and then rebooted. And now my monitor says Can't Display and I can't see the GUI. I can go to terminal (Pressing Ctrl + Alt + F1, F2, F3 etc) but Not the UI.