It doesn't allow me to install 10.5.2 on my ibook G4

What speed is your iBook (for example, 1.42 GHz or 800 MHz)? Leopard needs an 867 MHz or higher G4 to install. Just to be sure, you are using a legitimate retail DVD of Leopard, right?

Well, that answers that then. You need a full retail version of Leopard to install - the system restore disks that come from each system will only work on the system type they came with. Your MacBook system restores will only work with similar MacBooks, not your iBook.

I'm not sure what instructions you are talking about, but perhaps it was referring to Leopard itself which certainly IS compatible with PPC or Intel Macs- it is just the particular disk you are trying to use that is not usable with your iBook.

A regular retail Leopard disk will work just fine on the MacBook OR the iBook. BTW- the retail disks being sold now have the updated 10.5.4 on them too.

You don't HAVE to- when you start the installer on the Leopard disk you can do an "Archive and Install" type of install which will keep a lot of stuff (including most of the Users folder) in place, and will keep other stuff it is not sure of in a separate folder.

If you want a totally clean install, then you would use the option at the start of installation to "Erase and Install" which will format your drive first, cleaning off everything on it. For the most problem free installation of all this is the choice to make.

You could also choose "Upgrade", but that is the weakest choice for safety anyway, as it just updates the components of the existing OS installation and can turn out to have difficulties.

Always make sure you have a FULL backup of your existing data before using any of the choices unless you have nothing on the drive that you want to save.

You can not install an operating system older than your computer. Apple does not take steps to prevent it most of the time, but it usually won't install. This is especially true in mobile computers where components and drivers change from revision to revision.

edit_
dyslexia got the best of me, i was thinking you were asking about 10.2

hiddenpremise said:

You can not install an operating system older than your computer. Apple does not take steps to prevent it most of the time, but it usually won't install. This is especially true in mobile computers where components and drivers change from revision to revision.

Click to expand...

In this case the poster wishes to install an OS on an older Mac (the opposite of what you mention), and the issue is that the version that came on the install disk is the Intel-only one, not the PPC one that's also included on the official Leopard disks.

Duff-Man says....and again it seems to need to be said - even if you were able to install the Macbook disc version on your old iBook, you are not licensed to do so....oh yeah!