Mac LC 630 DOS Compatible and Performa 640

This relatively rare variant of the LC 630 includes a DOS card with an Intel 486DX2/66 CPU, although some shipped with a Cyrix 486/70. The DOS Compatibility card can share Mac motherboard memory or use its own dedicated RAM.

Performa 630The motherboard has two SIMM sockets, while the DOS card has a single SIMM socket. (The non-DOS 630 usually has just one SIMM socket.)

The 630/640 was quite cleverly designed for a computer with no industry standard slots. It contained an extended LC PDS that supports both LC and extended LC cards, a comm slot for a modem or ethernet card, and a video slot for either Apple’s Video System Card or TV/Video System card.

To top it off, the DOS card plugs into the CPU socket and also uses the PDS, but it leaves the comm and video slots free. Unlike other DOS Compatible Macs, the 630/640 doesn’t use a “hydra” video cable; both Mac and PC sides share the same video port. The DOS card also includes a joystick port, which plugs into the PDS socket.

Although the hard drive is IDE, the CD-ROM (when present) is a SCSI device.


  • introduced 1993.04.03 at $1,200; discontinued 1996.04.13
  • requires System 7.1 or later; highest version supported without a PPC upgrade is Mac OS 8.1
  • CPU: 33 MHz 68LC040 CPU; 66 MHz 486DX2
  • FPU: none, 68LC040 can be replaced with 68040 CPU
  • Performance: 12.5 (relative to SE); 22 MIPS
  • ROM: 1 MB
  • RAM: 4 MB on motherboard, expandable to 52 MB using two 80ns 72-pin SIMMs
  • DOS RAM: shared with Mac or a single 80ns 72-pin SIMM (up to 32 MB)
  • video: 1 MB VRAM, does not support portrait monitor
    • 512 x 384, 640 x 480: 16-bit
    • 800 x 600, 832 x 624: 8-bit
  • L2 cache: none
  • ADB: 2 ports for keyboard and mouse
  • serial: 2 DIN-8 RS-422 ports on back of computer
  • SCSI: DB-25 connector on back of computer
  • one LC PDS slot, one comm slot, one video slot, one TV tuner slot
  • size (HxWxD): 4.3″ x 12.6″ x 16.5″
  • Weight: 19 lbs.
  • PRAM battery: 4.5V alkaline
  • Gestalt ID: 98
  • addressing: 24-bit, 32-bit
  • upgrade path: Power Mac PDS card, 6300-series motherboard

Accelerators & Upgrades

Online Resources


  • Internal HD Format: Cannot See IDE Drives (Apple Knowledge Base 18360) notes that due to changes in the way modern IDE drives are formatted at the factory, early versions of Apple HD SC Setup (ones that come with System 7.5.1 and earlier) will not recognize them. You should boot System 7.5.2 or later and use Drive Setup 1.0.3 or higher with these drives.
  • The IDE controller only supports a single device.
  • This highest PIO mode this model supports is Mode 3 (11.1 MB/s), Macintosh: Using Third Party IDE Hard Disks
  • Serial port normally restricted to 57.6 kbps; throughput using a 56k modem may be limited. See 56k modem page. For more information on Mac serial ports, read Macintosh Serial Throughput on the Online Tech Journal.

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