Macintosh LC
The Macintosh LC is a low-cost Macintosh personal computer released by Apple on October 15, 1990.[1] The name "LC" stands for "low-cost color," and the machine was designed to bring color Macintosh computing to education and home markets at a more affordable price point than the Macintosh II series.[2] The internal codename "Elsie" was a phonetic play on "LC."
 | |
| Specifications | |
|---|---|
| Manufacturer | Apple Computer, Inc. |
| Type | Personal Computer |
| Released | October 15, 1990 |
| Discontinued | March 23, 1992 |
| Intro price | US$2,499 |
| CPU | Motorola 68020 @ 16 MHz |
| Memory | 2 MB RAM (expandable to 10 MB) |
| Storage | 40 MB or 80 MB SCSI HDD, 1.44 MB SuperDrive |
| Display | 512×384 (8-bit) or 640×480 (4-bit) |
| Sound | 8-bit stereo input/output |
| Dimensions | 2.9" H × 12.2" W × 15.3" D |
| Weight | 8.8 lbs (4.0 kg) |
| OS / Firmware | System 6.0.7 – System 7.5.5 |
| Successor | Macintosh LC II |
| Codename | Elsie |
| Model no. | M0350 |
Architecture and Processor
The Macintosh LC uses a Motorola 68020 processor running at 16 MHz. However, the system has a significant bottleneck: the 68020's 32-bit data bus is connected through a 16-bit memory controller, effectively limiting memory bandwidth.[3] This design decision reduced costs but limited performance compared to full 32-bit implementations.
The Gestalt ID for the Macintosh LC is 19.
Memory and Storage
RAM Configuration
The LC shipped with 2 MB of RAM standard, expandable to 10 MB. Memory expansion uses two 30-pin SIMM slots, which must be populated in pairs using matching SIMMs. The machine uses 100ns or faster SIMMs.
| Configuration | Slot 1 | Slot 2 |
|---|---|---|
| 2 MB | 1 MB | 1 MB |
| 4 MB | 2 MB | 2 MB |
| 10 MB | 4 MB + 2 MB onboard | 4 MB |
Video RAM
The LC includes 256 KB of VRAM standard, expandable to 512 KB with an optional VRAM SIMM. Video memory determines available color depth:
- 256 KB VRAM: 512×384 at 8-bit (256 colors) or 640×480 at 4-bit (16 colors)
- 512 KB VRAM: 512×384 at 8-bit or 640×480 at 8-bit
Storage Systems
Standard storage options included:
- 40 MB or 80 MB internal SCSI hard drive
- 1.44 MB SuperDrive (reads/writes 400K, 800K, and 1.44 MB disks)
Input/Output and Expansion
Port Configuration
- 1× Apple Desktop Bus (ADB) port
- 1× External SCSI (DB-25)
- 1× Audio input (3.5mm stereo minijack)
- 1× Audio output (3.5mm stereo minijack)
- 2× Serial ports (Mini DIN-8)
- 1× Video output (DA-15)
Expansion
The LC features a single LC Processor Direct Slot (LC PDS), a 96-pin expansion slot. This slot accepts LC-specific expansion cards including:
- Ethernet adapters
- Video capture cards
- Apple IIe Card (for Apple II compatibility)
Design and Form Factor
The LC introduced Apple's "pizza box" form factor—a compact, horizontally-oriented case designed to fit under a monitor. The case measures 2.9 inches high, 12.2 inches wide, and 15.3 inches deep. This form factor was used throughout the LC line and influenced subsequent compact Macintosh designs.
General Maintenance
For detailed maintenance practices including cleaning, PRAM battery management, and connector care, refer to the dedicated Macintosh LC General Maintenance page.
Troubleshooting
A comprehensive troubleshooting guide addressing common issues with the Macintosh LC is available on the Macintosh LC Troubleshooting page.
Capacitor Replacement
The Macintosh LC logic board contains 17 surface-mount electrolytic capacitors that commonly fail due to age. Detailed replacement guidelines can be found on the Macintosh LC Capacitor Replacement Guide page.
Technical Details
System Specifications
| Component | Specification |
|---|---|
| CPU | Motorola 68020 @ 16 MHz |
| FPU | None (not supported) |
| Data Bus | 32-bit (16-bit memory controller) |
| Address Bus | 32-bit |
| System Bus | 16 MHz |
| ROM | 512 KB |
| RAM | 2 MB (max 10 MB) |
| VRAM | 256 KB (max 512 KB) |