OS X crashes

[Ron Goebel]

Ok all you G4/OS X gurus out there, I have a problem.  I have a G4 
QuickSilver running OS X 10.2.5 with no problems until about a week 
ago.  Now, every 5 to 15 minutes, no matter what I'm doing, the 
screen darkens, as if a gray film is being pulled down from top to 
bottom, and a message says (in 4 languages): "You need to restart 
your computer.  Press and hold down the Power button for several 
seconds or press the Reset button."  The MAC address and local IP 
address of the G4 are at the bottom of the dialog box.

I've ruled out a hardware problem by virtue of the fact that I can 
boot into OS 9.2 and run just fine for hours.  Also, the problem will 
happen even if no applications are running.  I've even restarted and 
left it idle at the login screen, and within minutes the above 
happens.

So far, I've run Disk First Aid to both repair the startup volume and 
fix the permissions, run fsck at startup, zapped the pram, and run 
Drive 10 from the CD - all to no avail.

At this point I'm thinking I need to reinstall OS X 10.2 and then run 
the updater to 10.2.5.  However, it may be something as simple as 
trashing some preference file, if only I could figure out which one. 
Does anyone have any ideas about how to go about this task?  Oh for 
something like Conflict Catcher for OS X.

Ron