PowerMac G5 not showing boot manager or open firmware

Hmmm, seems to be pointing to a corrupt NVRAM, but I know of no way of fixing or overcoming that. 😟

This is a mystery indeed.

I recently got a PowerMac G5 Dual 2.5 GHz (7,3) from a friend of mine, and I would like to dual-boot it between Tiger (or Leopard) and Debian PPC. However, every time I try to bring up the boot menu (hold ALT/option at boot before chime) there is simply a black screen. Same happens when I try to boot to Open Firmware (hold CMD-ALT-O-F); just a blank screen.

I press these keys then I poweron the machine.

When I try to boot from the Debian CD, it's almost as though it is ignored, as I am put straight to OS X, but I can boot from the Panther/Tiger DVDs

cd was not compatible with the PPC. If the firmware does not find a compatible os on the cd, the cd is ignored. Try cd on another ppc.

Here are some idea:

1) Check for a later version of open firmware. Install.

2) Decide how much you want to mess with the machine. could turn it into a door stop.

4) Use unix nvram command to examine firmware variables. Maybe one is set incorrectly.

5) There are unix commands for partitioning hd. They are in 10.4.11 and later.

6) Install a boot manager. When I installed Linux on my iMag g3 600, the linux install put a boot manager on my linux partition. I created three partitions on the machine. I didn't need the linux boot manager. I didn't figure out all the ins and outs of the linux boot manager, yaboot.

Robert

Can you reset the NVRAM in Terminal?

Possible this is sometype of video problem with the firmware video driver ... hence the blank screen.

Robert

AHA, I wonder if this is a flashed PC card?

You can view and change nvram variables from the terminal. See man nvram

Try a different video card and display that are known to work with startup manager.

I forget in this long thread, but if it boots to a blank screen holding alt key, if you have an Install Disc inserted, or a bootable external drive, or another bootable partition...

Wait 30 seconds or so on the blank screen, press Right arrow then press enter.

Good work, great to hear, thanks for the report! 🙂

Great to hear!

Robert