If you have about 200 MB to spare on your PBs drive, that's all it takes to install OS9.
It will co-exist peacefully with OS X, no worries.

Testing the other RAM with the CD you found might be an idea as well, if the problem persists after the firmware-update.

POST stand for Power On self Test, and if the unit chimes, then it passes the POST.

Yes, you have to have a bootable and writeable os 9 volume to flash the firmware. That is becasue there is no apple os x flasher out right now. There are third party apps out there that let you flash firmware in os x, but I have little experience with them.

You could just load OS 9 on your system (which you need an os 9.1 folder anyways to run classic mode) boot into it and run the firmware update.

Or, if anyone has any more experience with a utility that will allow firmware flashes to be run in OS X, perhaps they can chime in and let us know.

Otherwise you will have to boot from an OS 9 HD. You can try holding down the option key and see if it will boot to an external firewire drive, or take it to a mac that has os 9 on it and try target mode booting it, however I think that the drive has to be an actual local disk to that. I have never tried.

That is no longer true. I did a factory recall job for apple once. They sent out 100+ imacs to our retail side all with bad batteries from the factory. Guess what, they all booted just fine with bad batteries. Apple also claimed it was an error in firmware that was causing the system to drain the battery way faster than intended to. So, I had to replace the back up battery in over 100 imacs, then flash the firmware on all of them.

Batteries just back up the PRAM settings when the machine has no power going to it. It does not hold any important information that would cause your system to not boot. Infact its been that way since OS 9, and perhaps even OS 8.6

OK, I understand mechanical hardware stuff, but I don't really think about the software side much, so bear with me. I'm going to load OS9 from the install disk that came with the PB. But that is 9.0 and I need 9.1. I looked on my G4 PB and sure enough there is OS 9.1 folder, so I must have it on the G3 PB too? But I can't boot from that can I? I'm guessing that I must somehow upgrade from the 9.0 install to 9.1 using the system folder I already have. But I have no idea how to do that.

I checked the hard drive on the G3 PB (running off the 9.0 install CD) and can't see the system 9 and system X folders like I do in OSX on the G4 PB. There is one generic system folder. Is that normal?

Can someone please explain this to me?

...meanwhile, my aiport extreme is being flaky, so i'll go post over there once i get it up again! arghh!

You must have an os 9.1 or higher system folder on your mac to run classic mode with in OS X. That is why you see a 9.1 folder on your OS X pb g4. OS 9 however is probably not installed. Installing it puts certain files in the boot sectors and modifies the file system a bit to let the system know that its bootable. Just having the os 9 folder on your rig does not mean its bootable to os 9, it just means there is a system folder that os x can use to emulate os 9. Hope that makes sense.

Just boot off your os 9 cd, install it, hop online and download the 9.2 combo update. Then run it, flash firmware, change start up disk to your os x folder, reboot, then see what software problems you have. Once you get it back up and running in os x, I suggest you pick up a copy of disk warrior, and run it to help fix any software issues. I cannot tell you how valuable disk warrior is, if you are a mac user its a must to have.

While I sincerely feel with you concerning the sad story you tell, I do know for a fact, that my LC 475 would not boot if the internal battery is flat.
As I said earlier, it would be helpful to have a list of all Macs with this problem. A Mac + will happily boot without a battery and you say iMacs as well. But between those two...

any system that came preloaded with os 9 or higher should not have any kind of issue where it will not power on or lock up if the back up battery goes bad. Anything with a G3 processor or greater should be in the same boat.

Those problems tend to be with the older power macs, like the performas and such, but even then batteries just caused irregular behavior and there was never a set pattern to it. Also apple no longer supports those products so you are limited to refurbished or used parts, whichs makes you even more limited trying to support those older macs.

IMO, old macs make good door stops or boat anchors, same thing with old PCs.

Thanks Guys! You are SOOO helpful! I am totally optimistic that my beloved G3 PB will be healthy again soon. I guess the download and update to 9.1 is rather obvious and simple.

tlarkin is correct about the internal battery not being needed for boot (PB or desktop). I've been running with mine disconnected for a few days now. OK, sometimes running. A guy on the apple discussions has encouraged many folks to disconnect it in order to fully reset PMU and he has many happy posters. So, it sounds like it can mess up the PMU and need a reset, but the state of being depleted or removed is not a problem.

I picked up disk warrior yesterday, but can't boot from it yet. I will definately run it once I can get that far. I'll also check those 512 RAM modules.

My firmware was current. The machine is running great in OS 9, but has problems in OS X. There IS a hardware difference. I have been using the original 64 MB RAM card. I tested each of the 512MB modules in OS 9. The first one I tried began to boot but then shut off. I tried it again and got 3 beeps. I also got three beeps with the other 512 module. So maybe the intermittent problems that have been deteriorating are gradual failure of these RAM modules?

Do you agree with me that the RAM is my problem? Is there something I am missing or not considering?

It seems suspicious that they would both fail at the same time after 4 1/2 years of use, and I am worried that something has caused them to fail. Or is that normal? When one starts to go it puts more load on the other or something.

Yeah now that you mention it I think it was due to the older Macs using ADB with the power button on the keyboard not working.

OS X is definately more picky than OS 9 when it comes to RAM. If it works in OS 9 and you get three beeps (incompatable ram) I would say that the problem is the ram. What caused this? No way to tell at this point. Unfortunately, we are now in a trial and error phase since all hardware pass the apple hw tests, and the only error you can produce is ram related.

Next step, swap out the ram with known good ram.