Okay, so this is seriously bumming me out. Whenever I pop in Fallout for a little game time it will always inevitably freeze, at first like after a half hour. Then ten minutes. Then five. Then one. Eventually it doesn't load the game. If I wait a day or two I can get another half hour or so, but it always happens. The thing is, all of my other games work fine. It's just this and Fallout 3. Can anyone please, please help?
EDIT: As a side note, installing to the HDD only makes the problem worse.
According to another thread, TES: Oblivion, FO3, and FNV all got an update at the same time, true or not, remains to be seen. This might be the problem in your case with FO3 and FNV.