I thought I'd seek some advice here... I have a nearly 5-year-old Powerbook G4, 1.3GHz, with 2 512MB RAM modules. I have already once had the motherboard replaced because the machine decided to stop reading one of the memory slots (an Apple Genius took it in for repair out-of-warranty, in spite of the fact that it's outside the serial number range for replacement). That was 3 years ago. Fast forward to today. Half the memory has gone missing again. I swap the modules - machine sees both. Reboot again, and poof! the module in the same slot disappeared (meaning: memory is OK, slot is bad). OK, it's a 5 year old machine. But this failure is a design defect. I like the MPB, and even though it's feeling a little pokey for some tasks, it works nicely and I don't really want to spring a grand + for a new laptop. Any suggestions?