G5 won't take new installation disc

You can't use the optical drive of a g5 on an Intel or vice versa, unless the drive is removed and put in an external firewire case for g5s, or supported USB case for Intels. You could just get a supported optical drive from http://www.macsales.com if the clock battery is good but the optical drive is not.

Looks like I have some stars to give back, then…. 😉

http://discussions.apple.com/thread.jspa?messageID=12006948&#12006948
http://discussions.apple.com/thread.jspa?messageID=7348067&#7348067
http://discussions.apple.com/thread.jspa?messageID=12553372&#12553372
http://discussions.apple.com/thread.jspa?messageID=8755997&#8755997

I'm not claiming it always works, and it particularly may not work in this case since there still could be something wrong with the Install DVD itself, but it is worth a try.

Maybe this tip is due for a revision. I don't know what exceptions work, and what do not.

In reading the section of your tip about what won't work because of dissimilar hardware, it sounds as if you might be mostly referring to the "traditional" way of setting up FireWire Target Disk Mode, i.e. setting up the computer with the bad DVD drive as the target, and the computer with the good DVD drive as the host. This will fail for dissimilar Macs, for the reason you mentioned:
-------
In Target mode, the target machine (the machine you held the T key down) is assumed by the installer to be nothing more than an external drive, to be a machine with the same configuration of the host machine because that's the only machine's firmware it can detect.
-----------------

But if you set up FireWire Target Disk mode "the other way," as I had suggested above, and as you also described in the earlier section of your tip, using the Mac with the good DVD drive as the target, and the Mac with the bad DVD drive as the host, then this potential hardware incompatibility issue does not arise. The host computer running the install DVD is the same computer that receives the new OS X installation. The computer with the good drive is not running anything at all - it is completely passive except for "lending out" its optical drive via TDM. You should therefore be able to use dissimilar Macs when connected in this manner, provided that the host Mac is otherwise suitable for the particular install DVD that is being used.

Whether there might be an optical drive hardware component in a particular computer that simply doesn't present an inserted install DVD as a bootable FireWire volume when that computer is booted into TDM is a separate question - it's certainly possible.

I am having the exact problem with my G5 as you described. For the life of me, I can not figure out how to make a "Start up" disk image on an external drive. Can you or anyone out there walk me through the steps to make an external HD into a start up disk image?

PS
Unlike you, I have been unable to get the **** Mac OSX Leopard disk (Apple Store bought) to mount in the G5.

TIA