Traditionally, older Macs used FPM non-ECC RAM, just as they used non-parity RAM (with the mysterious exception of a small number of parity-chipped IIci Macs, and the unmysterious exception of A/UX-running Quadra 950s). Some of the PPC Macs tolerated EDO, and a very few needed EDO.

There are larger concerns for use of 128MB cards in a Q 605:

http://macfaq.org/hardware/memory.shtml#Q2.4.6

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