Anyone out there have a similar issue? 1.8 iMac G5 works fine, then after a while the machine will not respond to commands, and I notice the Finder folders highlight in black. Weird. Cap's seem to be ok, though it's possible some are borderline issues, don't know as this is a first for me. Is this a PS or logic issue - can't be the hd, right? 3x LED's at boot, reset in O-F as well as Tech Tool gave everything a pass and the test ran 1-2 hours. Thanks.