Can you boot into safe mode? Since what you describe was about you forcing restart in the middle of a graphic driver update.
Plug the graphic card out, plug your monitor cable into the motherboard's just like many said here. If it boots then plug in your graphic card and update the driver in safe mode.
You may need to tweak some settings in the bios in order to make your display run in onboard graphic with graphic card plugged in.
Help PC can’t start