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 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           = 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]].

== 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."<ref name="sslc630">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.</ref>

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:90%;"
! Item !! Apple's figure
|-
| Macintosh processor || '''Motorola 68040''' at 33 MHz &mdash; 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.<ref name="sslc630" />

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

== References ==

<references />

[[Category:Apple Vintage Computers]]