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RAM DIMMs

The logic board has four 168-pin RAM expansion slots. At least one of the RAM expansion slots contains a factory installed SDRAM DIMM.

The RAM expansion slots accept SDRAM DIMMs that are 3.3 volt, unbuffered, 8-byte, non-parity, and PC-100 compliant. The speed of the SDRAM devices must be rated at 125 MHz (8 ns) or faster.

IMPORTANT

DIMMs with any of the following features are not supported in the Power Macintosh G3 computer: registers or buffers, PLLs, ECC, parity, or EDO RAM.

The 8-byte, 168-pin DIMM has one 64-bit-wide data bus per bank.

The minimum bank size supported by the Grackle memory controller IC is 2 MB, and the largest is 128 MB. The largest DIMM supported is a two-bank DIMM of 256 MB using 128 Mbit SDRAM devices. The maximum number of devices per DIMM is 16.

The SDRAM DIMMs can be installed one or more at a time. The logic board supports linear memory organization; no performance gains are seen when two DIMMs of the same size are installed. Any supported size DIMM can be installed in any DIMM slot, and the combined memory of all of the DIMMs installed is configured as a contiguous array of memory.

Presence Detect EEPROM

RAM Address Multiplexing

SDRAM Devices