I have an old graphite iMac that was running OS 8.6. I decided to try to install Panther on it. I booted the install cd and ran the installer. The installer told me that a firmware upgrade was needed and to reboot after the upgrade. Well, I ejected the CD and rebooted the iMac. Now the screen is black. The hard drive appears to boot then after about 2 minutes shuts down. I have tried plugging an external monitor into the VGA output, and the external monitor does receive a signal... but its just a white screen. I don't know what else to do! I've never had a problem with it before ;(