Macintosh Classic II
The Macintosh Classic II, released in 1991, was the final compact black-and-white Macintosh to use the classic all-in-one design. Unlike its predecessor, it utilized the more advanced Motorola 68030 processor—similar to the SE/30—but without the PDS expansion slot or 32-bit clean ROM. It came with 2 MB of RAM standard and supported up to 10 MB via a single 100 ns 30-pin SIMM. The Classic II retained the 9-inch monochrome display, making it ideal for schools and business use, but with improved performance and more modern architecture.
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| Macintosh Classic II | |
| Specifications | |
|---|---|
| Manufacturer | Apple Computer, Inc. |
| Type | Personal Computer |
| Released | October 21, 1991 |
| Discontinued | September 13, 1993 |
| Intro price | US$1,900 |
| CPU | Motorola 68030 @ 16 MHz |
| Memory | 2 MB RAM (expandable to 10 MB) |
| Storage | 1.44 MB 3.5" floppy drive, optional 40–80 MB SCSI hard drive |
| Display | 9" monochrome CRT (512×342 pixels) |
| Sound | Monaural 8-bit, 22 kHz |
| Dimensions | 13.2" H × 9.6" W × 10.9" D |
| Weight | 16.5 lbs (7.5 kg) |
| OS / Firmware | System 6.0.8L – System 7.6.1 |
| Predecessor | Macintosh Classic |
| Successor | Macintosh Color Classic |
| Codename | Performa, Stardust, Apollo |
| Model no. | M0420, M4150 |
General Maintenance
For details on disassembly, cleaning, voltage regulation, PRAM battery handling, and corrosion prevention, refer to the Macintosh Classic II General Maintenance page.
PCB Schematics & Service Manual
The Classic II consists of a logic board and analog board, similar in layout to the Macintosh SE/30 but with different ICs and no expansion slot.
Apple Service Manual
The complete Apple Service Manual archive is available at the Apple Service Manuals page. For the Classic II, you can download the service guide here:
Logic Board & Analog Board Schematics
| Logic Board | Analog Board |
|---|---|
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Capacitor Replacement Guide
The Classic II is prone to logic board failure due to surface-mount capacitor leakage. For safe replacement procedures, refer to the Macintosh Classic II Capacitor Replacement Guide.
Retrobrite
For plastic restoration and case whitening instructions, visit the Retrobrite page.
Troubleshooting
A complete guide to common issues including no chime, no video, checkerboard pattern, logic board failure, and hard drive detection issues is available at the Macintosh Classic II Troubleshooting page.