I recently upgraded my Ubuntu 12.04 to 12.10. But after everything installed perfectly, it tried to restart my PC. After that, a bit of console kind of a thing came (like the pre boot screen) and in that it asked me the username and password. I wrote the right details, still it said that the password is incorrect. Whenever I try to restart it, it starts a bit and then the monitor goes off and nothing happens. I have checked and rechecked all the connections but still the error is caused. Someone help me out, I don't want to waste more time!