I've been having this problem for a long time now and have found various, unreliable solutions each time. The basic problem is that my computer will turn on, the fans will turn on, the mouse and keyboard turn on, the CD drive turns on, the disk access light blinks, and everything seems to be working fine, but the monitor won't turn on. I'm using dual LG monitors, connected to one of my two NVIDIA 8600 GT graphics cards which are SLI'd together.
I have about a 1 in 100 chance of the monitor actually turning on (which is to say that out of about 100 tries just turning on and off the computer, the monitor will turn on). In the event that the monitor does turn on, I get the "windows did not start up correctly" error, at which point I try to run startup repair, with varying degrees of success.
About 1 in every 5 times, a system restore back to before I installed the updates on my computer will work. For the other 4 times, system restore will either fail, or when restarting the computer, the monitor again fails to turn on. However, when this does work, the updates which I had installed end up not installed, and the next time I shut down my computer, I have to repeat the same process again.
I've also confirmed that it must have something to do with the system updates. If I force shut-down my computer without installing updates, I have no problems turning it back on. I'll get the start-up message that windows did not shut down correctly, and I'll be asked if I want to start in safe mode, etc. However, picking "start windows normally" works just fine. Additionally, if instead of shutting down the computer I hibernate the computer, it also starts up just fine. The problem only arises when I click "shut down" and updates are installed. Any other form of shutting down or stand-by works just fine.
I've also tried unplugging everything from my computer except the monitors, keyboard, and mouse. This sometimes works as well, but in the end, I am still asked to install updates, and I have to repeat the whole process again.
I'm fresh out of ideas. Can anyone figure out what's going on? Thanks in advance.