I just upgraded Win 8.0 to Win 8.1 (please don't scold) and now FO3 (GOTY PC on CDs ed.) won't work. Before the upgrade, FO3 & all DLCs, FWE, EWE and PB worked fine. Mouse and sound worked fine. I had actually played through twice. After the Win upgrade, FO3 would boot up very slowly and jerky as far as the menu screen, then crash when selecting continue or start a new game. I deactivated and uninstalled everything to start over. I have now reloaded basic FO3 and all DLCs, used the video card "trick", changed the .ini to iAudioCacheSize=8192, turned off ingame vsynch, and applied the latest unofficial patch. I have been able to recover only minimally. I can get the game to run, but the video and audio are verrry slow, music stutters badly, and the mouse is extremely jerky and so unstable as to be almost useless. The game is unplayable; it hasn't actually crashed, but freezes up during character selection following the birth scene. I have internet-searched these problems extensively for clues, but am now stuck. Can someone please, please pleeeeezzzzz help? Thanks !!