[X4U] OS 9 on a G5?

Randy B.Singer randy at macattorney.com
Sat May 14 22:40:07 PDT 2005

Paul Moortgat said:

>An hospital which has a G4 with OS 9 on it with software running in 9 
>will replace it with a G5.  Is it possible to install OS 9 afterwards?  
>Or is a Mac Mini or eMac still with OS 9 because it's a G4?

Some Macintosh computers start up only in Mac OS X. These computers can 
run Classic, but they do not start up in Mac OS 9.


In September 2002, Apple announced that starting in January 2003, new 
Macintosh computers would only start up into Mac OS X, while retaining 
the ability to use most Mac OS 9 applications in Mac OS X's "Classic" 

These Macintosh computers only start up in Mac OS X:

    * PowerBook G4 (12-inch) and later models of 12-inch PowerBook G4
    * PowerBook G4 (15-inch FW 800) and later models of 15-inch PowerBook 
    * PowerBook G4 (17-inch) and later models of 17-inch PowerBook G4
    * Power Mac G4 (FW 800)
    * Power Mac G5
    * iBook G4 and iBook G4 (14-inch) and later models of iBook
    * iMac (Flat Panel) with serial numbers of xx303xxxxxx or later
    * iMac (17-inch 1 GHz) and later models of iMac
    * eMac (ATI Graphics) most models (see Note)
    * eMac (USB 2.0)

Note: eMac (ATI Graphics) models have Education configurations for 
CD-ROM, Combo and SuperDrive, which will boot into Mac OS 9. 

Unless things have changed recently, all new Macs come with OS 9 
installed so that you have the Classic environment to use.  (You have to 
have OS 9 installed to have Classic.  Having OS 9 installed does not 
necessarily mean that that you can boot into OS 9.  And, of course, all 
recent Macs cannot boot into OS 9.)

All recent Macs also come with a copy of OS 9 on their Restore Disks.

Recent commercial (that is: boxed) versions of OS X do not come with a 
copy of OS 9.  Until the release of Tiger (10.4) Apple had a program 
where you could purchase a copy of OS 9 for only $20 upon showing that 
you had just purchased the boxed version of OS X.  There is no sign of 
that program on Apple's Web site anymore.

If you have a computer that has OS X installed on it, but no copy of OS 9 
installed (which you need for Classic to run), you can install OS 9 after 
you have installed OS X:


You can purchase OS 9 on CD-ROM from Other World Computing for $37
You can download these free updates from Apple:

9.0.x to 9.1

9.1 or 9.2 to 9.2.1

9.2.1 to 9.2.2

Randy B. Singer
Co-Author of: The Macintosh Bible (4th, 5th and 6th editions)

Routine OS X Maintenance and Generic Troubleshooting

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