Macintosh LC

Macintosh LC

Macintosh 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

The Macintosh LC is a low-cost Macintosh personal computer released by Apple on October 15, 1990. 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. The internal codename "Elsie" was a phonetic play on "LC."

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. 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.

RAM Configurations

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

Macintosh LC Technical 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)