Apple Macintosh System 7.5 - Manual (Page 24)

Group upgrade Q&A
This section answers the most commonly asked questions about the group
upgrade to System 7.5. The answers here are brief; for details, refer to the
individual topics following this section.
Does System 7.5 work with all Macintosh models?
System 7.5 can be installed on all Macintosh and PowerBook computer
models except the Macintosh 512K, Macintosh 128K, and Macintosh XL.
System 7.5 requires a hard disk and 4 MB of internal random-access memory
(RAM). To use QuickDraw GX or PowerTalk, 8 MB of RAM is required.
Do I have to upgrade networked Macintosh and PowerBook computers to System 7.5 all
at once?
No. Macintosh and PowerBook computers using earlier versions of system
software can coexist on your network. However, you need to upgrade the
printing software on all computers that will be sharing LaserWriter printers,
using the Printer Update folder on the CD or the Custom Install option with
the Installer program. You also need to make sure that all computers have
network software that works with AppleTalk Phase 2.
Why must I upgrade printer drivers on Macintosh and PowerBook computers that won’t
be using System 7?
System 7.5 includes new versions of LaserWriter printer drivers that should be
installed on all Macintosh and PowerBook computers having driver versions
earlier than 7.0. (Version 7.0 and 7.1 drivers can coexist with the System 7.5
drivers on the network.) A special Installer file is included to simplify this
upgrade.
When a System 7 Macintosh or PowerBook prints on a LaserWriter that has
been initialized with an earlier printer driver, its driver causes the printer to
restart. While this process is harmless, it is time consuming and also clears
fonts from the printer’s memory.
21 Planning the Group Upgrade