Try Safe Mode, just turn the PC on and tap F8 about once
a second. Hopefully you'll get a menu with the option for
Safe Mode at the top. Press Enter twice and see if it
will boot now. Then log in and when prompted, click on NO
and run System Restore back to how it was. If the PC
keeps rebooting then you probably have a BSOD and the PC
is set to restart when the error comes up. You may be
forced to reinstall in this case
