I have a powerbook g4 1.25ghz 2 gig ram with newest version of leopord. For some reason when i view movies in full screen (even from youtube) my laptops seems to heat up very fast. Not sure if that's normal but after a while the whole system would crash. It never crashes if im doing low power work such as web surf or document editing, but when it comes to full screen movies, it starts to lock up. Anyone experiance this before and know the solutions to it?