Jim - Thanks for your suggestion. I have a hard time believing that a serious memory problem developed simultaneously with the software update. Up until that time everything was working perfectly . Nevertheless I haven't a better idea and I'm willing to try anything to avoid a reinstall. What utility are you referring to? I can't find anything in my system that looks like a hardware test. Is this something I need to down load or perhaps is it on the Panther system disk? For now I have to start up with my Firewire HD which has the full OS10.3.9 on it. Hope this won't make any difference to the test you suggest. as the original CD is with my other computer 2 hours away. John Erdman Sawtooth G4 AGP 400MHz, 704MB Ram, OS 10.3.9 iMac G5 2.0 GHz, 1GB Ram, OS 10.4.2 On Oct 9, 2005, at 23:52, Jim McMillan wrote: > I'm not so sure but the report suggests a memory issue. > Try refitting the memory. > then > Try startup from the OSX cd and run Apple hardware test. > Like I said but I'm not sure. I had similar reports and founds that > when I replaced the memory chip all was fixed. > GOOD LUCK > >