Things You'll Need
Instructions
Navigate to the "Fallout 3" folder by selecting "My Documents," "My Games" and "Fallout3." Locate the "fallout.ini" file within the folder.
Open "fallout.ini" with a text editor. Locate the line "bUseThreadedAI=0" and change the numerical value to "1." Create another line and enter "iNumHWThreads=2." This value will cause the game to use only two processor cores, preventing the game from freezing.
Click "File," and then click "Save" to save your changes. Open the game and test the new settings by playing through the game. If the game still freezes, press "Ctrl + Alt + Del" to kill the game process and make sure the values within "fallout.ini" were entered correctly.