Today I had to uninstall Avast from my relative's computer b/c it prevented Windows from displaying. It would display just right up to Windows landing in desktop then the labtop lcd would go black. So long story short, I had to go to safe mode and uninstall Avast which solved the problem. Specifically I believe the the 9.0.2011 update conflicted with the display drivers for the integrated intel 4500 mhd b/c a couple of days ago 9.0.2008 was working without incident on that machine. She never turns off her computer, she just uses sleep so, I guess today was the day where she restarted or whatever and the update finally hit.
If it is my computer I would have the patience to try to provide Avast log files and diagnostic information, but its not. However I still wanted to report it.