Macintosh Plus Memory Upgrade Guide: Revision history

23 September 2026

• curprev 18:2218:22, 23 September 2026 Josh talk contribs 4,927 bytes +123 Restore the memory layout diagram undo
• curprev 18:1418:14, 23 September 2026 Josh talk contribs 4,804 bytes +738 Sourced to Apple Macintosh Plus Service Source + Guide to the Macintosh Family Hardware: SIMM speed corrected 120ns -> 150ns or faster (Apple); 2.5MB config corrected (1MB pair in Bank A, 256K pair in Bank B - page had 1MB in A with 256K described as Bank B incorrectly); R8 identified as the 256K BIT resistor and R9 ONE ROW added; eight-chip and complete-row rules added; refs and reflist undo

19 April 2025

• curprev 13:2113:21, 19 April 2025 Josh talk contribs 4,066 bytes +70 No edit summary undo
• curprev 13:2113:21, 19 April 2025 Josh talk contribs 3,996 bytes +70 →Common Issues and Troubleshooting undo

8 April 2025

• curprev 23:3023:30, 8 April 2025 Josh talk contribs 3,926 bytes +30 →Additional Resources undo Tag: Visual edit

4 April 2025

• curprev 17:1417:14, 4 April 2025 Josh talk contribs 3,896 bytes +41 No edit summary undo

19 March 2025

• curprev 16:4016:40, 19 March 2025 Josh talk contribs 3,855 bytes 0 No edit summary undo Tag: Visual edit
• curprev 16:3416:34, 19 March 2025 Josh talk contribs 3,855 bytes +6 No edit summary undo Tag: Visual edit
• curprev 16:1216:12, 19 March 2025 Josh talk contribs 3,849 bytes +10 No edit summary undo Tag: Visual edit
• curprev 16:1116:11, 19 March 2025 Josh talk contribs 3,839 bytes +343 No edit summary undo Tag: Visual edit
• curprev 16:0716:07, 19 March 2025 Josh talk contribs 3,496 bytes −8 →Additional Resources undo Tag: Visual edit
• curprev 16:0616:06, 19 March 2025 Josh talk contribs 3,504 bytes +3,504 Created page with "The Macintosh Plus originally shipped with '''1 MB of RAM''', which was a significant improvement over earlier compact Macintosh models. However, many applications and system software updates required additional memory to function efficiently. Fortunately, the Plus supports memory upgrades up to '''4 MB''', vastly improving performance and usability. === Memory Specifications === The Macintosh Plus uses '''30-pin SIMM (Single Inline Memory Module)''' chips. Below are t..."