This article comprises the Macintosh System 7.5.3 Revision 2 Overview and Installation file.

Who should install System 7.5.3 Revision 2?

Apple is recommending that only customers with specific system software and Macintosh computers update their systems with System 7.5.3 Revision 2. There is no benefit for other customers.

The only systems which will benefit from System 7.5.3 Revision 2 are as follows:

• 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

1. Make sure you are in the Finder.

2. Choose About This Macintosh from the Apple menu. The system software information is in the About This Macintosh window.

What is System 7.5.3 Revision 2?

System 7.5.3 Revision 2 is a set of system software enhancements that improves the reliability and performance for the computers described above.

When you install System 7.5.3 Revision 2, you get the following enhancements:

• Better reliability for PowerBooks using RAM Doubler. If you have a PowerBook using system software 7.5.3, and use RAM Doubler (version 1.6.1 or earlier), you may have experienced a problem when waking your PowerBook from sleep. This software fixes this problem.
• Overall performance enhancements for PowerBook 2300 computers and PowerBook 500 or Duo series computers with the PowerPC Upgrade Card installed.
• Improved reliability when using PC-formatted floppy disks with PowerBook 500 series or Duo series computers with the PowerPC Upgrade Card installed. If you have a PowerBook 500 series or Duo series computer with the PowerPC Upgrade Card installed, PC-formatted floppy disks that were formatted on your computer may be unreadable in DOS or Windows computers. This software fixes this problem.
• Improved reliability on PCI-based computers (Macintosh 7200, 7500, 7600, 8500, and 9500 computers) and PowerBook 5300 computers, PowerBook 2300 computers, and PowerBook 500 or Duo series computers with the PowerPC Upgrade Card installed.
• Improved reliability when copying files to a 1 gigabyte hard disk. If you have a PCI-based computer with a 1 gigabyte drive, this software helps avoid problems when copying files to the hard disk.
• Improved reliability when using the Startup Disk control panel. In rare instances, when you turn on a PCI-based Power Macintosh computer it may not start up from the disk selected in the Startup Disk control panel. This software fixes this problem.

Note that if you have an AppleVision monitor, you should install "AppleVision Fix 1.1" before you install this update.

When you install this software, an extension called Startup Tuner is installed in your Extensions folder. This extension ensures that your computer will correctly start up from the disk selected in the Startup Disk control panel.

It is recommended that you run the Disk First Aid application found on the "Disk Tools" disk that shipped with your computer. Double-click the Disk First Aid icon and follow the instructions on the screen. Disk First Aid checks your hard disk for problems. If you have a problem using Disk First Aid, see the manual that came with your computer.

Installing System 7.5.3 Revision 2

Before you install System 7.5.3 Revision 2, your computer should have System 7.5.3 installed or System 7.5.2, PowerBook Enabler 1.2 or later installed. To find out what system software version your computer is using, follow the steps in "Who should install System 7.5.3 Revision 2" above.

Follow these steps to install System 7.5.3 Revision 2:

1. Open the Extensions Manager control panel.

2. Choose either "System 7.5.3" or "System 7.5.2" from the Sets pop-up menu (one of these two choices will appear, depending on the version of system software your computer is using).

3. If you have third-party peripherals that are required for installation and that require an extension, turn those extensions back on. (Examples include video drivers, alternative input devices, network card drivers, and removable media.)

4. Restart your computer.

5. Insert the System 7.5.3 Revision 2-1 disk into the floppy disk drive, and double-click its icon to open it.

6. Double-click the Installer icon to open it.

7. After you read the licensing agreement, click Agree to continue with the installation.

8. Make sure that the destination disk indicated on the screen is the one on which you want to install system software. If the wrong disk name appears, click the Switch Disk button until the correct disk name appears.

9. Click Install.

10. Follow the instructions on the screen. On-screen messages tell you when you need to insert the other disk.

11. When the installation is complete, Click Restart to restart your computer.

12. Use the Extensions Manager to turn on additional extensions (you'll need to restart your computer for the extensions to work). If you encounter problems, choose the set of extensions you chose before the installation (see step 5), restart your computer, then turn on extensions one at a time to determine if one of them is incompatible.