PATHHardware Documentation > Power Mac G4 Developer Note


Expansion Issues

The expansion features of the new Power Mac G4 computer are similar to those of the previous Power Mac G4 computer.

Internal Storage Devices

Standard configurations of the Power Mac G4 computer include two unused expansion bays in the bottom of the enclosure. The expansion bays accommodate 1.6-inch-high 3.5-inch devices. Power connectors are provided for both expansion bays. For more information, see Disk Drives.

RAM Expansion

The main logic board uses JEDEC-standard SDRAM DIMM cards that are 64-bit bus, nonparity, 168-pin, 3.3-volt, unbuffered, and PC100 compliant. The speed of the devices must be 125 MHz (8 ns) or faster.

IMPORTANT

DIMMs with registers or buffers, DIMMs with PLLs, and DIMMs with EDO RAM are not supported in the Power Mac G4 computer.

The maximum supported height of SDRAM DIMM cards is 2 inches. The maximum number of devices supported on a DIMM is 16 SDRAM devices. For more information, see RAM Expansion.

No L2 Cache Expansion

The backside L2 cache is integrated into the microprocessor module. Cache expansion is not supported.

Proprietary Modem Slot

The 70-pin modem connector in the Power Mac G4 computer is the same as the connector on the modem slot in the previous Power Mac G4 computers. The modem slot is a proprietary design specifically for Apple modem cards.


© 1999-2000 Apple Computer, Inc. – (Last Updated 04 Feb 00)