Macintosh Performa 640CD DOS Compatible
 | |
| Macintosh Performa 640CD DOS Compatible | |
| Specifications | |
|---|---|
| Manufacturer | Apple Computer, Inc. |
| Type | Personal Computer |
| Released | May 1, 1995 |
| Discontinued | February 1996 |
| Intro price | US$2,199 |
| CPU | Motorola 68040 @ 33 MHz + Intel 80486DX2 @ 66 MHz |
| Memory | 8 MB Mac-side RAM (4 MB built in + 4 MB SIMM), max 52 MB; 4 MB on the DOS card, max 32 MB |
| Storage | 500 MB IDE hard drive, 2× CD-ROM, 1.44 MB floppy drive |
| Display | Supports up to 832×624 at 8-bit color |
| Sound | 8-bit mono input, 8-bit stereo output (16-bit in CD mode) |
| Dimensions | 4.3" H × 16.5" W × 12.6" D (10.95 × 41.95 × 32 cm) |
| Weight | 19 lbs (8.6 kg) |
| OS / Firmware | System 7.1.2P – Mac OS 8.1 / MS-DOS 6.22 / Windows 3.1 |
| Predecessor | Performa 630CD |
| Successor | Power Mac 6100 DOS Compatible |
| Codename | Crusader |
| Model no. | M3076 |
The Macintosh Performa 640CD DOS Compatible is a dual-platform personal computer manufactured by Apple Computer and released on May 1, 1995.[1] It combines the Performa 631CD with an Intel 486DX2 processor card, allowing the computer to run both Mac OS and DOS/Windows applications.
The Performa 640CD DOS Compatible was not sold in the United States and was marketed primarily in international markets.
Dual-Platform Architecture
The system features two processors:
- Macintosh: Motorola 68LC040 @ 33 MHz
- DOS/Windows: Intel 486DX2 @ 66 MHz on a PDS card
Users could switch between Mac and DOS environments, with the DOS card appearing as a virtual PC within the Mac OS.
DOS Card Specifications
- Intel 486DX2 processor at 66 MHz
- Dedicated RAM (up to 32 MB)
- Shared use of display, keyboard, and mouse
- Includes MS-DOS 6.22 and Windows 3.1[2]
The DOS card occupies the LC PDS slot, leaving the comm and video slots available for other expansion.
Memory and Storage
Mac RAM
8 MB standard with two 72-pin SIMM sockets for expansion up to 52 MB total.
DOS RAM
The DOS card has dedicated RAM expandable up to 32 MB independent of Mac system RAM.
Storage
- 500 MB IDE hard drive (partitioned for Mac and DOS)
- 2× Apple CD 300i plus CD-ROM drive
- 1.44 MB SuperDrive floppy (accessible from both environments)
Display and Graphics
1 MB of dedicated DRAM for Mac video. The DOS card provides VGA-compatible graphics.
Bundle Contents
- Modem
- Apple display (varies by market)
- Keyboard and mouse
- MS-DOS 6.22
- Windows 3.1
- Mac consumer software bundle
General Maintenance
For maintenance procedures, refer to the Macintosh LC 630 DOS Compatible page. General maintenance is covered on the Macintosh LC 630 General Maintenance page.
Capacitor Replacement Guide
See the Macintosh LC 630 Capacitor Replacement Guide page.
Troubleshooting
See the Macintosh LC 630 Troubleshooting page. For DOS-specific issues, refer to Macintosh LC 630 DOS Compatible.
Apple service data
Apple treats the Performa 640 DOS-Compatible as the Macintosh LC 630 DOS-Compatible with a different bundle, and says so in terms: "treat LC 630 DOS-Compatible information as applicable to the Performa 640 LC DOS-Compatible unless specified otherwise."[3]
| Item | Apple's figure |
|---|---|
| Macintosh processor | Motorola 68040 at 33 MHz — the full 68040 with its floating-point unit, not the 68LC040 of the plain 630 series |
| DOS processor | Intel 80486DX2 at 66 MHz on a DOS-Compatible board |
| Macintosh memory | Ships with 8 MB on the main logic board (4 MB built in plus a 4 MB DRAM SIMM in one slot); maximum addressable 52 MB (4 MB built in, a 32 MB SIMM in one slot and a 16 MB SIMM in the other) |
| DOS memory | Ships with a 4 MB SIMM; maximum addressable 32 MB on the DOS-Compatible board |
| SIMM type | Both boards require 72-pin, 80 ns or faster SIMMs |
| Processor-direct slot | Occupied. A DOS-Compatible adapter board fills the LC processor-direct slot and provides a DB-15 connector for a PC/AT game controller |
| Hard drive | 500 MB IDE |
| Sound | 8-bit monophonic input; 8-bit stereo output (16-bit in CD mode) |
| Maximum power | 45 W, not including the monitor |
| Case | Height 4.3 in., width 16.5 in., depth 12.6 in.; 17 lb / 19 lb with CD-ROM |
There is also a separate DOS-Compatible sound board in this machine, which Apple lists as its own replaceable module alongside the DOS-Compatible board and the adapter board.[3]
See Also
References
- ↑ Macintosh Quadra 630, Wikipedia—link(accessed 2026-02-10)
- ↑ Performa 630 and LC 630, Low End Mac—link(accessed 2026-02-10)
- ↑ 3.0 3.1 Apple Computer, LC 630/Quadra 630/Performa 640, Service Source. Hosted here as LC 630/Quadra 630/ Performa 640 Service Source (File:Quadra.lc_630.performa_640.pdf). Specifications chapter.