I installed Ubuntu 13.04, but after the reboot theres only a black screen with the blinking bar on the top left. I found, that one possible solution is that the video drivers are not installed, so i tried it (the weird thing is that "try ubuntu without installing" works perfectly fine). So i downloaded the .run file, but it's always saying "seems like you're running a X Server" blahblah. I searched for maybe 2 hours for the solution, but none of the ones i found worked for me. Can anybody please help me? PS: I'm pretty new to Ubuntu...