I've been playing Fallout New Vegas without issue since launch, I was playing last night as well, no later than 10 hours before. I went to sleep and woke up to find that steam had downloaded a patch, and that my game now crashes on start up every time. The launcher will run, I press play, it shows the screen with all the legal text regarding copyrights and trademarks of the brands and such, then crashes. Sometimes it'll make it past that to the Bethesda logo screen, but that's rare and seems to be unrelated to anything I do.

The patch was: "Preferences, quicksaves, and autosaves should behave normally. Cloud support currently disabled."

I'm running on Windows 7 x64 with nVidia GeForce 8800GT, Intel Core2 Duo 2.66 GHz, 8GB RAM, with a dual screen set up.

I've tried: restarting computer, verifying game cache, defragging game files, updating graphics driver, installing d3d9.dll fix, using compatibility to Vista SP2, and turning off any anti-virus.

So far none of the above fixes have made any change to the current crashing behavior. I'm forced to believe that the patch is the source of the issue since it's the only thing that's changed between last night and today, but I've not seen anyone else complain of any similar crashes after the patch was launched. Is anyone else having anything similar? Any ideas?

Do you have any of the preorder packs or other mods? If so, try setting your FalloutNV.ESM's "Date Modified" attribute with http://www.petges.lu/download/download.html to a date before the game came out. Older files load first, so if Steam replaced your FalloutNV.ESM and a preorder or other dependent file is older than its master, the game would crash at startup.

I actually tried removing the d3d9.dll file, I've had it in for a while as a solution to the stuttering frame rate when in a crowded area, and have had no issues. Removing it seemingly resolved the crashes, though I don't know why, since as I said, I have been playing for a few days with it active. I'm not sure if this leaves me back to square one with the stuttering frame rate bug, but I'd rather have that than an insta-crash to desktop when starting up.

That solution you have may work however, JustinOther, as I do have the Caravan Pack from preordering steam. I'll give it a try.