In line with its new policy of frequent, incremental system upgrades, Apple Computer announces MacOS System 7.5.4 this week--and sounds the last OS roundup for some older Macs.
The update is a set of software enhancements, the most significant of which is a revised version of virtual memory, which results in significantly better performance when performing some tasks (such as launching an application), especially for PowerPC-based systems using SCSI drives.
This improvement will vary greatly depending on the amount of RAM installed in the system, the amount of virtual memory allocated, and the applications being used. All users will benefit from reliability enhancements, including the elimination of one cause of the dreaded Type 11 errors.
This update, the third since March, fixes in place Apple's new standardised number of system software releases. From now on, if major architectural changes are being delivered, the first digit of the version number will be incremented. If new features are added to a system software reference release without major architectural changes, the second digit will be incremented. When system software updates are delivered with only reliability and performance improvements, the third digit will be incremented.
This update is Apple's last for the Macintosh Plus, SE, Classic, Portable, PowerBook 100, SE FDHD, SE/30, LC, II, IIx and IIcx. These computers were not designed to support 32-bit memory addressing, which will be required by all future Mac OS releases. The update will also only install on computers currently running System 7.5.3, including System 7.5.3 Revision 2.
The update will be automatically mirrored to Apple's New Zealand ftp server on release, and should be available via http://www.apple.co.nz or ftp://ftp.apple.co.nz/ by Friday or Saturday. It will appear subsequently on the next Apple software update CD.