Mac IIci

Building on the success of the Mac IIcx, the IIci offers 56% more power in the same compact case. A new feature was integrated video. The big advantage: Users no longer needed to buy a separate video card. The big disadvantage: The built-in video uses system memory (this is sometimes called “vampire video”).

“…may be the best machine Apple has ever produced.” MacUser, November 1989.

Macintosh IIcx/IIci

Macintosh IIcx/IIci

Built-in video replaces the Macintosh II High Resolution Video Card (25 MHz motherboard video vs. a 10 MHz NuBus connection) and supports 8-bit color on a 640 x 480 screen as well as 4-bits on a 640 x 870 Portrait Display. Depending on bit depth, this uses between 32 KB and 320 KB of system memory. Also, Byte reports (Oct. 1989) that because the CPU and video share the same memory, the CPU is shut out of accessing RAM during video refresh, reducing performance by up to 8%.

Our own tests on a IIci show that although CPU performance does increase slightly when using a NuBus video card, video performance with an unaccelerated video card is about half as fast as the built-in video. Unless you need to support a larger screen or have an accelerated video card, overall performance may be worse with a video card than with internal video.

Still, adding a video card was a popular way to increase performance and free precious RAM; another boost came from adding a level 2 (L2) cache. This proved so popular that Apple eventually made a 32 KB cache standard.

The Mac IIIIx, and IIcx all run a 16 MHz CPU on a 16 MHz motherboard with a separate 10 MHz bus for NuBus cards. Byte mentions (Oct. 1989) that the IIci runs its CPU and RAM at 25 MHz, NuBus at 10 MHz, I/O subsystems with a third oscillator, and onboard video with a fourth oscillator. By decoupling various subsystems this way, it was easier for Apple to boost the CPU and RAM speed without redesigning every part of the motherboard.

The IIci also has the fastest SCSI bus in the Mac II series, topping out at approximately 2.1 MBps throughput.

The IIci was the first Mac to support the 68030’s burst access mode, which “allows the CPU to read 16 bytes of data at a time in about half the clock cycles. This results in [a] . . . 10 percent improvement in performance.” (Byte, Oct. 1989, p. 102)

The IIci was the first Mac with “clean” ROMs, allowing 32-bit operation without special software. Along with the Mac Portable, it was the first Mac to use surface mount technology.

Upgrade Advice

The IIci is a best buy because of the numerous upgrade options:

  • If you don’t have a cache card, buy one for $20-30 on the used market – unless you plan to add an accelerator card in the 68030 PDS.
  • If you’re running low on RAM, by all means buy more. You should have at least 8 MB, but more is much better (unless you’re sticking with System 6, in which case you can’t use more than 8 MB).
  • Buy an accelerated NuBus video card if you’re using internal video. $30 and up on the used market. This will free up to 320 KB of system memory. See our NuBus Video Card Guide for video card profiles.
  • Quadra 700 motherboards are uncommon. For that level of performance, consider a 68040-based accelerator, such as the Sonnet Presto 040 (40 MHz 68040 with 128 KB L2 cache, see our benchmark page). See a more complete list of accelerators below. Note that you will have to perform surgery on your case with the Quadra 700 motherboard upgrade.
  • A newer hard drive will be far more responsive and have far more capacity than the one that shipped with the computer. Any 3.5″ half-height or third-height drive will fit.
  • More RAM plus Speed Doubler equals improved hard drive performance through intelligent caching.


  • introduced 1989.09.20 at $6,700 ($8,800 with 40 MB hard drive); discontinued 1993.02.10
  • code names: Pacific, Aurora II, Cobra II
  • model no.: M5780
  • Gestalt ID: 11
  • upgrade path: Quadra 700

Mac OS

  • requires System 6.0.4 to 7.6.1
  • addressing: 24-bit or 32-bit

Core System

  • CPU: 25 MHz 68030
  • FPU: 25 MHz 68882
  • ROM: 512 KB
  • RAM: 1 MB, expandable to 128 MB using 4-SIMM banks of 80ns 30-pin memory; can use 256 KB, 512 KB, 1 MB, 2 MB, 4 MB, 8 MB, and 16 MB SIMMs
  • L2 cache: optional, later 32 KB standard


  • 3.5 without cache, 4.3 with cache, relative to SE
  • 6.3 MIPS
  • 2.05, MacBench 2.0 CPU
  • 6.98, Speedometer 3.06
  • 0.40, Speedometer 4
  • 1896 Whetstones
  • see Benchmarks: IIci for more details


  • built-in 8-bit video, supports 512 x 384 and 640 x 480 at 8-bits or portrait monitor (640 x 870) at 4-bits (uses 64-320 KB of RAM for video, not separate VRAM)
  • video port: DA-15


  • Hard drive: 40 or 80 MB SCSI
  • floppy drive: 1.4 MB double-sided
  • floppy connector on back of computer


  • ADB ports: 2
  • serial ports: 2 DIN-8 RS-422 ports on back of computer
  • SCSI ports: DB-25 connector on back of computer
  • sound: 8-bit stereo
  • NuBus slots: 3
  • PDS/cache slot: 1


  • size (HxWxD): 5.5″ x 11.9″ x 14.5″
  • Weight: 13.6 lbs.
  • PRAM battery: 3.6V half-AA
  • power supply: 159V

Accelerators & Upgrades

  • adding a video card frees up to 320 KB of RAM and increases application speed
  • 32 KB level 2 cache (which became standard in later production runs) – most accelerators occupy the cache slot, which means removing the L2 cache
  • Quadra 700 motherboard (25 MHz 68040), requires case surgery
  • MicroMac Diimo/030 (50 MHz 68030), 64 KB cache, optional 50 MHz 68882 FPU
  • MicroMac Carrera (33 MHz and 40 MHz 68040), optional 128 KB cache
  • MicroMac 90 MHz Carrera (45 MHz 68040)
  • Sonnet Technologies Presto 040 (40 MHz 68040 or 68LC040), optional 128 KB cache (see benchmark)
  • Daystar 50 MHz 68030 with 68882, discontinued
  • Daystar Turbo 040 (33 MHz, 40 MHz 68040), discontinued
  • Daystar Turbo 601, 66 MHz and 100 MHz versions, discontinued (resource: Unofficial Turbo 601 Site)

Discontinued accelerators (68030 unless otherwise noted) include the Applied Engineering TransWarp (50 MHz 68030, 25, 33 MHz 68040), DayStar Universal PowerCache (33, 40, 50 MHz), Fusion Data TokaMac SX (25 MHz 68040), Logica LogiCache (50 MHz), Radius Rocket (25 MHz 68LC040 to 40 MHz 68040), TechWorks NuBus (33 MHz 68040), and Total Systems Magellan (25 MHz 68040).

Accelerator Reviews

Online Resources


  • Never connect an Apple II 5.25″ floppy drive to the Mac’s floppy port. Doing so can ruin the floppy controller, meaning you can’t even use the internal drive any longer.
  • Internal video on the IIci and IIsi, and the Mac II mono and color video cards, will not work with multisync monitors, whether Apple or PC style. Griffin Technology made the Mac 2 Series Adapter, which works with Apple’s Multiple Scan monitors and most Mac compatible monitors. There was also a version for using VGA-type monitors on older Macs.
  • Serial port normally restricted to 57.6 kbps; throughput with a 56k modem may be limited. See 56k modem page. For more information on Mac serial ports, read Macintosh Serial Throughput in our Online Tech Journal.
  • When using internal video, RAM from Bank A is used for video. During video refresh, the CPU is prevented from using Bank A. For best performance, largest SIMMs should be in Bank B if you are using internal video.
  • Internal video may reduce system and serial performance; a NuBus video card is recommended.

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