Editing Macintosh Performa 640CD DOS Compatible

{{Infobox computer
| name         = Macintosh Performa 640CD DOS Compatible
| image        = [[File:Macintosh_LC_630.jpg]]
| caption      = Macintosh Performa 640CD DOS Compatible
| manufacturer = Apple Computer, Inc.
| type         = Personal Computer
| release date = May 1, 1995
| discontinued = February 1996
| price        = US$2,199
| cpu          = Motorola 68LC040 @ 33 MHz + Intel 486DX2 @ 66 MHz
| memory       = 8 MB Mac RAM + 8 MB DOS RAM (expandable)
| 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        = Stereo 16-bit sound input/output
| dimensions   = 4.3" H × 12.6" W × 16.5" D
| weight       = 19 lbs (8.6 kg)
| os           = System 7.1.2P – Mac OS 8.1 / MS-DOS 6.22 / Windows 3.1
| predecessor  = [[Macintosh Performa 630CD|Performa 630CD]]
| successor    = [[Power Macintosh 6100 DOS Compatible|Power Mac 6100 DOS Compatible]]
| codename     = Crusader
| model        = M3076
}}
The '''Macintosh Performa 640CD DOS Compatible''' is a dual-platform personal computer manufactured by Apple Computer and released on May 1, 1995.<ref>{{cite web |url=https://en.wikipedia.org/wiki/Macintosh_Quadra_630 |title=Macintosh Quadra 630 |publisher=Wikipedia |access-date=2026-02-10}}</ref> It combines the [[Macintosh Performa 631CD|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<ref>{{cite web |url=https://lowendmac.com/1994/performa-630/ |title=Performa 630 and LC 630 |publisher=Low End Mac |access-date=2026-02-10}}</ref>

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]].

== See Also ==
* [[Macintosh LC 630 DOS Compatible]]
* [[Macintosh Performa 631CD]]
* [[Macintosh Performa 630CD DOS Compatible]]

== References ==
<references />

[[Category:Apple Vintage Computers]]