G4 Quicksilver suddenly will no longer boot OS 9.2.2 from any device, but OS X is fine

[cplum]

I have a G4 Quicksilver (2002). I just got the power supply repaired and it seemed to be working fine. The internal drive is partitioned into two bootable volumes. One has a fairly new and clean install of 10.4.11 and 9.2.2, and the other a very old and not very clean install of 10.5.8 and 9.2.2. When I first got it up in running again and installing the repaired power supply, I had no issue booting the various OSes from both partitions, including OS 9. However, after running OS X for a while, I decided to boot into OS 9, and when I did the boot failed. I just got a blank screen (not black, more like a blue gray). No happy mac, sad mac, blinking folder, or anything.

I then booted into open firmware. Reseting nvram didn't help. I then saw the multi-boot command and tried that. It showed both of my partitions. The one I was trying to boot into showed up as an OS 9 volume and the other OS X, which makes sense since those were the currently selected startup OSes on each volume. I chose the OS X volume and it booted with no problem. After booting I set the startup disk to OS X on the volume that wouldn't boot into OS 9, and it booted with no problem. I then tried booting into OS 9 on the 2nd partition, and just like with the first partition it hung very early on in the boot. So I used multi-boot to boot into OS X again. I inserted the OS 9 installer CD that shipped with the G4, selected it as the startup disk, rebooted (and held down the C key for good measure). Same issue. Just a blue/gray screen. I then rebooted and went into Open Firmware and tried multi-boot again. This forced ejected the OS 9 installer CD. I put in the OS X installer CD, did a refresh from the multi-boot screen, and it showed the OS X installer CD and let me boot from it.

So it appears my G4 just won't boot OS 9 off any disk, even a CD. Any idea why?

One thing to add is that between my initial testing (after replacing the power supply) and when this problem started, I had been using Disk Utility a lot to make disk images of the two volumes and also opening (and verifying) older disk images of the volumes. I've been having this issue where newly created disk images would not verify, so I was doing a lot of experimenting with them. Not sure if that might be related.

Also, I had a firewire drive hooked up most of this time, but it's been disconnected ever since I started having this boot issue.

 

[cplum]

BTW, I also verified with Disk Utility that OS 9 drivers are installed on the disk that the two partitions are on, and also installed on the OS 9.2.2 Installer CD. I then tried booting an OS 9.2.2 partition from the firewire drive, and it has the same problem (and I also verified that it has OS 9 drivers installed).

This seems like it is probably some sort of Open Firmware issue, but I did all the following resets and that hasn't fixed the issue:

reset-nvram
set-defaults
reset-all

 

[cplum]

Problem solved. It was the SCSI card. I had removed it while repairing the power supply since it was a bit in the way. When I did all my testing after repairing the power supply, I had not yet installed the SCSI card. Once everything was working I went to shut the service door and then realized I still had to put the SCSI card back in. I did that, shut the door, and went on to just use OS X for a day or so. It wasn't until I then decided to boot into OS 9 that I realized there was an issue, and by then had completely forgotten that the SCSI card was the one thing that had changed since I last booted into OS 9 successfully.

Anyway, not idea what the problem is with the SCSI card (nothing is attached to it). I swapped it with the SCSI card from my other G4 (which current itself is down itself with a broken power supply) and it worked, so there definitely seems to be something wrong with the card that affects OS 9.