I have been using Ubuntu for several years, but this is the first time I have had a problem like this. When I upgraded from 12.10 to 13.04, every time I boot into Ubuntu and the login screen is supposed to show up, my screen remains black. I can't see any part of the login screen. Typing on the keyboard and moving the mouse doesn't help at all. The same happens when I lock my screen and walk away. When I come back, no keyboard or mouse movement bring the display back up. The only way I have overcome this is by using my keyboard's "brighten the screen" button. Only then does the screen the login or lock menu. I was hoping that at some point, an update would fix the problem. But as of now, it has stayed the same, and I have been putting up with it for nearly three months. Why does 13.04 cause my laptop screen to go black? Is there a way to fix it?
The laptop in question is a HP Pavilion dv4-2160us Entertainment Notebook