> 
> In response to this one, I have had the same trouble with my PowerMac 8600/300. I believe that it boils down to a tired power supply. My machine takes forever to get from the black screen (and chimes) to get to any kind of operating system. Running LinuxPPC, my machine rechimes (is that a word?) 3 times before it starts to boot. If I'm wrong on this please correct me. I'd really like to take care of this problem on my box as well.

If this occurs after powerup it could also be that your harddisk has not spun-up yet. 
There is an openfirmware command sequence that tries a few times until it properly boots.
Maybe this is what you're seeing?

Robert.