Powerbook booting only with command key

My 15.2" 1.25ghz Powerbook (all stock the SD model) will only boot if I hold down the command key after the chime (but only sometimes). If I don't press it the SD will engage and then the HDD will spin up but then the HDD will spin down. I also am unable to boot from an external FW400 HDD (by holding down Option key)***this is something I need to do***.

It still does this after I wiped my Panther install and re-installed Jag (I have the upgrade discs) for a while, then I erased and installed Panther (now running 10.3.4) and it still does want to start on its own - so I don't think it's a software issue ('cause of the 2 fresh installs of Jag & Panther).

However I think it might be something stored in the PRAM or NVRAM and I'd like to know some other ways to reset them.

I can't reset the PRAM (cmd-opt-P-R) because it shuts down right after I hit the power button or boot into Open Firmware to manually try and reset it.

So, is there something else I could do (a manual button or something)?

Please Help,
-Thanks

 

Well the problem was the logic board (it getting fixed now). Anyone else have this happen to them? Right now I'm waiting for a new screen, the 1st replacement (for white spots) was damaged during shipping to the dealer.