My Power Macintosh computer included System 7.5.3 pre-installed on the hard drive. However, I have heard that the pre-installed version of System 7.5.3 is not the same as the version of System 7.5.3 that you get by installing System 7.5 Update 2.0.

Does this mean I also need to install System 7.5 Update 2.0?

Do I then need to install System 7.5.3 Revision 2 as well?

Can I skip System 7.5 Update 2.0 and just install Revision 2?

What is System 7.5 Version 7.5.3?

Question : Does this mean I also need to install System 7.5 Update 2.0?

Answer: Although your computer has System 7.5.3 pre-installed, you should still install System 7.5 Update 2.0. This udpate includes some additional fixes that are not included with the pre-installed version of System 7.5.3. After installing System 7.5 Update 2.0, you should then install System 7.5.5 Update.

Alternatively, you can download and install System 7.5 Version 7.5.3 which includes the updates and fixes found in System 7.5 Update 2.0 and System 7.5.3 Revision 2. You can then install System 7.5.5 Update.

Question : Do I then need to install System 7.5.3 Revision 2 as well?

Answer: Revision 2 is a set of six system software enhancements that improves the reliability and performance of some computers using System 7.5.2 (on PowerBook computers ONLY) and System 7.5.3. If you have one of the computers listed below, you should install System 7.5.3 Revision 2 AFTER installing System 7.5 Update 2.0. If your computer is not listed, you can still install System 7.5.3 Revision 2, but it will not provide you with any benefits. System 7.5.3 Revision 2 does not need to be installed before installing System 7.5.5 Update because the fixes from Revision 2 are in System 7.5.5 Update.

• All PowerBook systems using Connectix RAM Doubler
• All PowerBook 5300 and PowerBook Duo 2300 systems
• All PowerBook 200 or 500 Series systems which have been upgraded with the Macintosh PowerBook Processor Card Upgrade Kit with PowerPC (or upgraded with similar third party products)
• All Macintosh 7200, 7500, 7600, 8500, and 9500 systems

Answer: No. System 7.5.3 (pre-installed), System 7.5 Update 2.0, and System 7.5.3 Revision 2 do NOT contain all of the same fixes. So, if your computer requires System 7.5.3 Revision 2, then you should first install System 7.5 Update 2.0, then install System 7.5.3 Revision 2, and then install System 7.5.5 Update.

Alternatively, you can download and install System 7.5 Version 7.5.3 which includes the updates and fixes found in System 7.5 Update 2.0 and System 7.5.3 Revision 2. You can then install System 7.5.5 Update.

Question : What is System 7.5 Version 7.5.3?

Answer: System 7.5 Version 7.5.3 contains all the updates and fixes for System 7.5 into one installer that can be used on any Macintosh computer that supports System 7.5. It contains the fixes from System 7.5 Update 1.0, System 7.5 Update 2.0, and System 7.5.3 Revision 2.

System 7.5 Version 7.5.3 is available for downloading from the Apple Software Updates web site at http://www.apple.com/swupdates .

It unites all the various flavors of 7.5.3 into one installer that can be used to install on any Mac OS computer.

For additional information about the fixes included in System 7.5 Update 2.0 and System 7.5.3 Revision 2, read the following articles in the Tech Info Library:

Article 20005: System 7.5 Update 2.0: System 7.5.3 Differences
Article 19134: System 7.5 Update 2.0: What's New in This Update
Article 19944: Macintosh System 7.5.3 Revision 2: FAQ

Software updates mentioned in this article can be found by searching the Apple Software Updates web site at http://www.apple.com/swupdates .