Similar problem.:
Fujitsu Lifebook NH532 w/
Windows 8 pro
HD 4000
i5-3210, 6GB RAM
The computer came w/ Win7HP, and I immediately upgraded to Win 7 Pro. Both had no display problems. Sometime after upgrading to Windows 8, I get no display instead of the screen for my password. From reading all the other comments, my best guess is that the driver got screwed up at some point when I had the computer connected to a projector and started it. I have tried deleting the current driver and installing various drivers, new and old, - all with no luck. I'm not too interested in messing around with the registry, or the other more exotic fixes that were suggested here. For now, I have to put the computer to sleep and wake it up again every time I boot it.
Intel - please fix this!