The Mac Plus shipped from Apple in a 1MB configuration:
  • 4 - 256K SIMMs

The Mac Plus can however, be Upgraded two SIMMs at a time as follows:

  • 1, 2, 2.5, and 4MB configurations


The minimum speed for SIMMs is 120ns, however, I recommend that you use 150ns, 30pin SIMMs, for a 4MB configuration.

Contact Newer Technologies(1-800-678-3726) for these SIMMs, as they are quite available and inexpensive:

  • The part number is 7MM1MX8-60s

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