My COD4 game will always freeze when im playing but it flucuates on how long i can play until it freezez, this also happens to my biohock and assasins creed, but my halo3 works perfectly wrong, has anyone else had this problem or no how to fix it

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my COD4 freezes random times, playing time doesn't matter.

haven't touched Assassins Creed in 3 months. COD doesn't leave the console

Maybe your GPU or CPU gets too hot (> 100 degrees celsius) and it slows down automatically to avoid damage. That might cause some games to freeze.
Download some program that allows you to monitor your PC's temperature sensors and look for values above 80 degrees celsius after some time of playing a game like COD 4.