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Question about how "Universal" MacOS Installers work.

macuserman

Well-known member
If I install Mac OS on a PowerPC machine using a "Universal Installer" would that drive then be able to boot in a 68k machine as well? Or would it not include the 68k bits because it is installing from a PowerPC machine?

I'd like to be able to move a drive from a PowerPC machine into a 68k one due to ease of installation if that will work, but wasn't 100% if that would work, or if I need to do something special to make sure that the 68k stuff also got installed so that it would work once transferred.
 

MrFahrenheit

Well-known member
It depends. I've seen it work, and I've seen it not work.

It seems it more depends upon the other devices you have and their extensions, as well as the disk driver used by SCSI.

For Iomega drives, the Iomega extension updates the driver on the disk when you use the PowerPC version, which makes that disk not bootable on a 68K Mac unless you reformat it on a 68K Mac again, and re-copy the system software back over.

It took me a long time to figure out what was happening with my Zip and Jaz cartridges working on 68k, booting up on a PPC, and then no longer booting a 68k Mac. It's possible there are other devices this happens to as well.
 

CC_333

Well-known member
For Iomega drives, the Iomega extension updates the driver on the disk when you use the PowerPC version, which makes that disk not bootable on a 68K Mac unless you reformat it on a 68K Mac again, and re-copy the system software back over.
I discovered that this problem can be negated almost completely, at least for Zip, by formatting the Zip disk with a non-Iomega driver (I found that the patched Apple HD/SC Setup driver and Lido's driver to work well, and I'm sure others do too) and dispense with the Iomega extension, which would no longer be needed.

I was able to get a Zip disk, appropriately formatted and configured with compatible SSW, to reliably boot a Mac Plus, which is difficult to impossible when using Iomega's drivers, depending on version (I believe version 4.2 of the Iomega driver is reported to work on the Plus, but I'm not sure).

c
 
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