I just installed the Dead Money Add on. I have all the other add ons installed and played through already. I have about 125 hours put into this game. Once i get into the bunker i am locked in but when i get to the room with the gas vents, i get gassed and the screen goes black. No loading or anything, just a full system freeze. I have installed and re-installed both the game and the add ons. I cleared the system cache and deleted other large installed games. Nothing seems to help. What can i do to fix this?