In case any Fallout 3 gamers didn't know this trick to stop game freeze and PS3 lock ups, I want to share info that could end most of your game freezes.
- delete game DATA,not the SAVE files (optional)
- load a save file to continue a game
- bring up your Pipboy
- Then pause (hit start)
You should see the "Save" option unavailable or "grayed out", then you'll see the HDD yellow light showing activity, since this could take 10 to 30 mins of game data installing to the HDD, enjoy doing something in the mean time.
Check you PS3 HDD yellow light to see if disc activity stopped, if so then the game should be ready to play without locking up.
It worked PERFECTLY for me after I pushed thru Point Lookout and then resuming the story mode and the game play was very smooth. My game didn't even freeze when I had Dogmeat or Fawkes following me and V.A.T.S. didn't lock up either.
For the note, I got an old fat PS3 with a 320gb HDD and I have 15mb size saves and nothing was affected.
Hope this helps.