Intel Mac Mini won't see external for startup disk

[StacyC1]

I have a new Leopard Mac Mini that I was hoping to be able to use to run 10.3.9 and 10.4.11 systems off my external.

I made sure to format the external (with 2 partitions) as GUID before I copied the older OS's onto it. But when I go to choose one as startup disk, the Mini won't give me either of them as an option.

Is this a basic conflict between old OS and new Intel architecture, or is there hope for me?

Thanks.

[Giaguara]

10.3 doesn't support GUID - there was nothing that shipped with intel hardware before late 10.4.
And if the 10.4.11 is older than what your Mac Mini shipped with, also out of luck.

[StacyC1]

Thanks for the quick reply. Guess I'll be nursing my G4 Powerbook along for a while then.

[ElDiabloConCaca]

To expand a tad on what Giaguara's helpful post says: any new Macintosh computer will not be able to run any version of the operating system that is older than the one it shipped with.

This means that if your Mac mini shipped with Leopard 10.5.4, then you cannot use Leopard 10.5.3, 10.5.2, 10.5.1, 10.5.0, or any prior system to boot the computer. In a lot of cases, you won't even be able to use a retail version of 10.5.4 to boot the computer.

In short, you must use either the System Restore CD/DVD that came with the computer or a retail version of Mac OS X that is higher than the one that shipped with the computer to boot it.