I have a faithful iMac G4 that will now now longer boot up. I'm constantly getting Kernal panics during the boot up process, but in differing places. Sometimes it's while the grey apple is on screen, sometimes when the screen has gone blue just after. Once in a blue moon it actually loads the operating system only to kernal panic a minute or two later. So I booted into single user (after looking on the web) and ran fsck -f and it said there was a segmentation error, I then ran /sbin/fsck fy after reading official apple support documents and looking around a bit more and found that this is apparently what your supposed to type (i'm not a command line guy) and it said all was ok. Each time I ran it it said the HD appears to be ok. So I booted up with the Tiger install dvd and it kept kernal panicing again and again (at this point i'm thinking - damn it it's going to be hardware related) finally the dvd booted and I ran disk utility to verify the disk and it said the HD was ok. I decided to do a repair permissions and then went to the bathroom (I was getting ready for work) only to come back to a kernal panic. That was the last thing I did and I'm now at work. Usually my computer is turned on constantly, occasionally every few weeks or so I restart it due to software updates or just because I hadn't done it for a while. All these problems started after I turned the computer off and unplugged it for an hour or so while some electrical work was done in the bathroom (new switch for the shower). The only other thing different about the machine is that about 4 months back we installed a new dvd burner as my superdrive had given up the ghost. An engineer friend who knows his stuff did it for me (with me watching, wincing as he pried apart my machine, It is my baby after all ) and all went fine. So please anyone out there have any ideas?