Apparently there is a problem with the disc of CoD4. Unfortunately I cannot read the topics i saw at another forum as they are websensed, but I'll post them here, so anyone can read if there's some truth behind this.
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EDIT: I just read this:
I have a 40GB one, but I don't know if this post is trustworthy? Don't know what's the hype anyway?IT's the 90nm CELL not the GPU. The 90nm RSX GPU is tried and proven technology. RSX-like chips have been running in PC's for years. The problem lives with the 90nm Cell chip, COD4 will pushs the 90nm Cell harder than any game before, the chip will heat up and the heat will not move out of the PS3 quick enough cause failure. the Cell will die and the power supply and the Cell will not communicate anymore. 40 gig PS3's are not having this problem becasue they use a 65nm Cell Chip that is faster and cooler.