First time post to this list. Brief introduction, my name is Scott Thurmond (Scott was already taken by someone who describes himself as the list mom) and I'm an FDA toxicologist (not drugs folks, foods), and long time Mac user (although the FDA insists on running Windoze). Anyway, I have an older desktop G4 500 Mac (forgot when they came out, but bought mine shortly there after) that has been working well until yesterday when I rebooted (Mac OSX, the last iteration of the original OSX). It got past the initial boot sequence and stopped (producing a nice blue screen, not what I was looking for, but pleasant all the same). Ran disk utility and the boot disk seems fine (although I realize this is a basic check). I'm unable to get past this pleasant blue screen even after reinstalling OSX and restarting in safe mode. Any suggestions for diagnostic software, or for other uses for this boat anchor? Thanks.