Macintosh LC 475
The Macintosh LC 475 is an entry-level 68LC040-based Macintosh desktop that was released in October 1993. Most 475s used an updated version of the original LC case design that better matched Apple's "Espresso" design language, but early production units used the original design.
The 475 is essentially identical to a Quadra 605, aside from the processor used - in fact, all it takes is flipping a jumper on the logic board to make a 475 identify as a Quadra.
Specifications
| Spec | Details |
|---|---|
| Release Date | October 1993 |
| Discontinuation Date | May 1994 |
| Processor | Motorola 68LC040 @25MHz FPU: No Bus Speed: 25MHz |
| RAM | 1x 72-pin SIMM Slot - 4 or 8MB Standard - 132MB Maximum |
| Hard Disk | 3.5" SCSI - 80, 160, or 250MB Standard |
| Graphics | 512KB or 1MB VRAM |
| Audio | Internal Speaker |
| Internal Drives | Manual-inject 3.5" 1.44MB Floppy Drive |
| Expansion | 1x LC III PDS Slot |
| Networking | None |
| Other I/O | - 1x ADB - 2x Serial - 1x DB25 SCSI - 1x DB15 Video Out - 1x Line Out - 1x Mic In |
| PRAM Battery | 1/2AA Lithium |
| Original Mac OS | System 7.1 |
| Maximum Mac OS | Mac OS 8.1 |
Upgrades
CPU Upgrade
The 68LC040 CPU can be easily swapped out to a full 68040 with an FPU. PowerPC 601 upgrade boards were also available.
SSD Upgrade
Check our page on SCSI SSD replacements for more info.
Resources
 Service Manual |
 Logic Board Schematic |
Capacitor Reference |
|---|
Common Faults & Maintenance
PRAM Battery Leaks
The Macintosh LC 475's Lithium PRAM battery is highly prone to leaking and should absolutely be removed. Unlike most other Macs, the 475 does require to working battery to boot properly.
Capacitors
The LC 475's logic board has several surface-mount electrolytic capacitors on it that leak corrosive fluid with age. These must be replaced for reliable operation.
The LC 475's power supply also usually needs recapping for the same reasons - especially if you have the TDK PSU, which used ELNA brand caps.
Other Notes
Most original SCSI hard drives for these have gone bad, especially those made by Quantum, which suffer from sticky rubber bumpers in the head assembly.
The Mac LC 475's case yellows with age. A retrobrite process can be used to correct this, if it bothers you. The plastic is also getting brittle.
Page last updated (MM/DD/YYYY): 03/11/2025
Update Reason: page rewritten
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