No strange noises. The install CD's diagnostics show the drive to be SMART capable and it shows the drive as good. Another symptom is: When the system boots, the initial Apple splash screen is now a striped dark grey, instead of the light blue it once was.
I am fairly certain that the boot loader (or the Mac equivalent) has become corrupted. It started when I installed a Safari update and rebooted. Is there a way to rebuild this?
Chuck
PS: I was able to boot with Ubuntu and copy all of my important files off when this first began. My data is safe, thankfully.