Hi there and thanks in advance. I have a 1.5GHz 15" powerbook running 10.4.8 that has been pretty reliable in the (almost) 3 years I've had it. But then this fall I was getting kernel panics, freeze-ups, etc. and the Apple Store replaced the hard drive. All was good for about 5 months and then I got kernel panics again. They said it was 3rd party RAM. Removed it, but there's still a problem (when running the Disk Utility I get this msg: "First Aid failed" and "Error: The underlying task reported failure on exit," and they now want to replace the hard drive again. Is there anything that could be making my hard drive(s) die? I would like them to deal with any problems before my AppleCare expires in May. What does the logic board do? (a friend suggested having them look at it...) I'm not a computer guy, so know little about how this equipment works. One last note. The only other thing I noticed during the 5 good months: every once in a while I would have something weird happen, for example when using the Finder I would be unable to rename folders until I restarted the machine. Or, occasionally using Mail, options I normally set in preferences would disappear, and I would have a different looking set of "New Message" options, as if I had changed my preferences, though I hadn't. These seemed like little things and I never dealt with them because things seemed to go back to normal, but perhaps they were symptomatic of something larger? Any advice appreciated. I'm taking my computer in tomorrow or Sunday to have them replace the hard drive, and just want to relay as much info to their techs so they check out everything. Thanks again!