Got an interesting problem here guys (and girls). Hopefully someone can point me to the likely cause. I have a friend with a G4 500, and every time you try to turn it on or restart the computer, it comes up with a grey screen after a few moments that says "You need to restart your computer". I've tried restarting while holding down the X key which should have forced it to start up using Mac OS X . I tried restarting while holding the Option key. I picked the Mac OS X system disk, but I got the same "you need to restart your computer" message. I even tried resetting PRAM by shutting down the computer, turning it back on while pressing Command-Option-P-R. Nada. Any ideas? Im really trying to avoid a re-install of the system if I can help it.