I don't have an answer for you, but it sounds like either a firmware problem or a memory problem. Have you installed any third-party memory SIMMs in the machine?
If you haven't done so already, I suggest you post on the appropriate Discussion on the Apple website Support tab. Hope you get it gigured out.
Hello,
My problem is to get OS X 10.4.8 to boot, I always have to reset my PRAM (OPTION + CMD + P + R). I hold down the combination keys and release it when I hear the second chime. That's the only way I can get into OS X, and everything else like safe mode, verbose, etc.
To make it clear, before I can boot in OS X with or without any bootup keys held down, I always have to do an extra step by first holding down OPT + CMD + P + R to reset the PRAM.
If I just power on my powerbook g4 and don't hold any bootup keys or reset the pram, it shows the Apple Logo then the screen blanks out before I see the spinning gear.
Also I can only boot from my Install CD from time to time. The Drive would read it sometime and sometime it just speeds up then speeds down and I don't hear any reads or writes from the Drive and HD.
Any help is appreciated. Thank you!
PS I tried every solution out there. From Open Firmware to unplugging the HD and booting from the CD. You name it, I tried it.

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