Well I
appear to have found the fix, but I'm still annoyed.... why buy a quad core, when a game released a considerable amount of time after quad cores hit the shelves cannot cope with it!!!!!!!!!!
A guy posted this on the Bethseda

forums, and it worked for everyone that tried it. I guess it makes the AI use a different thread, and limits the threads to 2, effectively giving me a dual core processor.
I had tried going to one core, still the crash, so I guess the AI had something to do with it as well, and this is the strange thing... it only happened in empty houses, so maybe a memory leak with the AI code or something? In basic terms,
- Code: Select all
If AI_present == 0 then
Crash
Annoy the shit out of customers because we are a bunch of incompetent fuckwits
Moan like a little girl when our next game is pirated rather than purchased
Go out of business and get a job at McD's
End (Using Task Manager)
Anyway, all that aside, find your fallout.ini file in username/documents/my games/fallout 3 (at least in Vista) and add/change the following lines... the first line should already be there, change it and add the second line.
bUseThreadedAI=1
iNumHWThreads=2
I have been running around a small house for ages without problem, before it was always less than a minute.
Now to start a new game....