I would also suggest a clean boot: http://www.thewindowsclub.com/what-is-clean-boot-state-in-windows
You can leave anti-malware and steam service checked.
CHeck the event viewer. http://windows.microsoft.com/en-us/windows/open-event-viewer#1TC=windows-7
Look under windows logs. CHeck both sys and app logs. You can clear them and recreate the problem.
See if anything comes up. Just right click the logs and select the clear log.
Hi, I was also having trouble with my ASUS laptop running a 960M. Just found a fix by disabling my intel 4400 in the device manager through the control panel. The blackscreen was being caused by fallout not using the 960M. Disabling the Intel forces it to use the Nvidia card.
Not sure if that will help in your situation but just wanted to share.
Good luck!
*Edit
I spoke too soon Doing this gets me past the blackscreen problem. The main menu runs great, the intro plays fine and then when I get to the character creation screen the game runs at 1fps
Will keep trying. In my case its some problem with the game finding the GPU :/