Here's the case.

My Computer can boot ubuntu 13.04 but the time it loads my unity session --I have set autologin, the video card chrashes and the monitor blacks out.

Even if I go console to do the job, because of the autologin, it again chrases.

Then I decided to go to the single login by adding single on the kernel parameter on grub at boot. It again crashes. But when I try to boot to windows, everything works out just fine.

Ps: I have also tried to use nomodeset on the kernel parameter. I have also guessing that the gpu HAD overheated because when I touched the gpu it is really hot. I have nvidia geforce GT220. I have also done this at dawn.