I am in the main questline, right after you tell Swank that you're going to take Benny out in the Tops casino.
After activating the elevator to the 13th floor, the screen goes black and the console becomes unresponsive. This bug was mentioned on the Fallout wiki but no solution was given.
Note that when I took the elevator to search Benny's room, the game didn't crash. It's only when I try to take it the second time.