Help! My iBook has been acting more and more strangely for the past few days -- first it was Safari "unexpectedly quitting," then freezing. Then I got a very scary-looking kernal panic type message, though not in the usual box at the middle of the screen. It was in the upper left, as if I had logged in in single user mode, superimposed on the normal screen. I blithely ignored this and restarted, though I did use "carbon copy clone" to create an complete clone of my entire computer on my external hard drive. Today I stupidly (given that the computer has already been acting very oddly) allowed Softwear Update to convince me to download two security updates without noting exactly what they were. (Before I go any further -- I believe I'm running 10.3.9, though it may be 10.3.7. This is a 40GB dual usb iBook from 2003, has already had the motherboard replaced once, with third-party RAM.) Anyway, I left my computer apparently happily downloading, and came back a while later to find the screen saver image frozen with the dreaded black-square multilingual kernal panic message. I restarted and the hard drive started to spin very very fast, with a shrill whine, and the screen never got past the question-mark file. I restarted again. This time the screen stayed black. Same shreeking whine. I panicked and restarted again. This time it got all the way through the grey apple startup, the general blue-bar startup screen, and hung at the final item in that lineup -- "Login Window starting." And there it's hung ever since. I read on one of the archived messages that in a similar situation someone suggested booting in single-user mode and typing "fsck." I did that and it found a place where there was one of something rather than two. It said that it repaired it. I tried restarting. Same problem. I am at a loss. I don't remember how to boot off a separate computer and run disk utility that way. Past experience suggests to me that this is a hardware issue, but I'm keeping my fingers crossed that it's not. Help! I'm not a techie! What do I do? While I'm waiting for a response I'm going to take out my third-party RAM and see if that helps, but somehow I don't think that's it. Thanks in advance.