My fallout games have stopped working after I upgraded from a gtx 260 to a gtx 560. I have checked the drivers even went back to the oldest driver on nvidia's site. I really love to start play it was a great game.
I have both those games on steam and have had a lot of problems with crashes. Fallout 3 is unplayable because it will crash every few mins. I have looked for solutions with no success. When you say "wont work" do you mean the games wont start or they start and then crash?
For fallout 3 it won't even start without crashing and fallout new vegas it goes to the graveyard scene and then crash
well now both load the game but when i try to start a new a game it crashs try the d3d9orig.dll file didn't work, tried deleting the intro scene from fallout_default.ini but that didn't work either, but my friend that i give my 260 to he plays it just fine
the problem isnt graphics drivers. bethesda has made this game almost ocmpletely unplayable on a machine made after 2008 when the game came out and they really dont give a shit about fixing it themselves. it's a cpu/ram issue and you can try to fix it yourself here
http://forums.nexusmods.com/index.php?/topic/202013-fallout-3-crashes-fixreduce-guide/
as for new vegas it was really buggy on launch but if you have the steam copy it should work fine right out of the box. if mods are your trouble, reinstall and play vanilla, adding in mods slowly to find the culprite
It runs ok for me with a FX8320+HD7850 all be it useing huge amounts of the video cards vram for a old game but i did see some haveing problems that disabled the cpu core's down to 2 cores and had success running the game that way.
But i am gessing its a nivida driver error.