Specifications

CHAPTER 1
Introduction
Compatibility Issues 11
DAV Slot 1
The digital audio video (DAV) slot in the Macintosh Performa 6400 computer is
compatible with Power Macintosh 5400, 7600, 8500, and 9500 computers. However, it is
not compatible with the DAV slot in the Macintosh Quadra 660AV, Macintosh Quadra
840AV, Power Macintosh 6100, 7100, and 8100 computers, nor is it direct plug-in
compatible with the DVA (digital video application) slot in the Power Macintosh 5200
and 6200 computers. The DAV slot is a 60-pin slot with additional signals and
capabilities. A 40-to-60 pin adapter cable provides backward compatibility with DVA
cards developed for the Power Macintosh 5200 and 6200 computers. For additional
information about the DAV slot, see “The DAV Connector” beginning on page 53.
Expansion Slots 1
The I/O expansion slots in the Macintosh Performa 6400 computer are PCI expansion
slots and are not compatible with PDS expansion cards for the Macintosh LC family of
computers, the Macintosh Quadra 630 computer, or with cards that operate in the I/O
expansion slot in Power Macintosh 5200 and 6200 computers.
Cards that are incompatible with the I/O expansion slot include
■ cards with drivers that include incompatible code. Some drivers that do not follow
Apple Computer’s programming guidelines won’t work on machines that use the
PowerPC 603 microprocessor. For example, some of those drivers write directly to the
cache control register in an MC68030. Such code won’t work on a PowerPC 603
microprocessor.
■ cards with drivers that include code to check the gestaltMachineType value and
refuse to run on a newer CPU. The idea is to protect users by refusing to run on a
machine that the cards haven’t been tested on. Such cards have compatibility
problems with all new Macintosh models.
RAM Expansion 1
The Macintosh Performa 6400 computer uses JEDEC-standard 168-pin DIMMs (dual
inline memory module) DRAM cards rather than the 72-pin SIMM DRAM cards used in
the Power Macintosh 5200 and 6200 computers. For information about DRAM DIMM
configurations supported on the Macintosh Performa 6400 computer, see “RAM
DIMMs” beginning on page 42.
DRAM DIMM developers should note that the PSX memory controller on the main logic
board of the Macintosh Performa 6400 computer does not provide support for 4 M by
4-bits (12 by 10 addressing) or 1 M by 16-bits (12 by 8 addressing) DRAM devices.
RAM DIMM Dimensions 1
Apple Computer has made the following change to the mechanical specification for the
RAM DIMM.