PS2 Freezing ?

[THAB]

Hello
I have a scph-50004 with messiah mo-chip.
sometimes when i play games (DVD) the game is freezing after a while.
in games like "rise to honor" , "Resident evil : Code veronica" , "Resident evil : dead aim" , "resident evil : Outbreak" , "True Crime" .
freesing time is not same. sometimes after 1 hour and sometimes after 3 houres !
What is the problem ?
is it possible the problem is heating ?
please help !

[Uchiha Sasuke]

I never had a problem with freezing with my ps2, even with the early model. I think it might be your mod-chip that is causing the problem.