Apple Macintosh IIci

Desktop Computer

Released on September 20th, 1989, the IIci was part of the Macintosh II family of computers from Apple, essentially being an upgraded version of the IIcx. Some of the main features include integrated video hardware, a 25 MHz 68030 CPU (up from the 16 MHz on the IIcx), a maximum of 128 MB of RAM, and a built-in SCSI hard drive. The IIci was discontinued on February 10th, 1993, after about 3 years and 5 months of production.

There are two IIcis at JCS. Both are entirely functional as of July 2015, after some repairs mentioned below.


  • Motorola MC68030 CPU and 68882 FPU @ 25 MHz
  • 8 RAM slots, allowing up to 128 MB of 80ns 30-pin SIMMs (default 1 MB or 4 MB)
  • First Mac with a "32-bit clean" ROM, allowing for true 32-bit addressing, and thus up to 128 MB of RAM
  • Integrated stereo audio, with 22.255 kHz sample rate and 8-bit sample width
  • Integrated video, supporting 512 x 384 and 640 x 480 resolutions with 8-bit color or 640 x 870 with 4-bit color
  • 3 NuBus expansion slots
  • 1 cache expansion slot
  • SCSI hard drive (default 40 MB or 80 MB)
  • 1.44 MB floppy drive
  • Easily disassembled case, with only a single holding screw (though there is an additonal optional screw that can secure the top cover)


There is a very common problem of vintage Macs that had affected both of my IIcis: the surface-mount electrolytic capacitors had leaked their corrosive electrolyte onto the motherboard. If left too long, this liquid can dissolve the board's traces and solder joints, potentially causing connections to be broken. Luckily, the problem on both was not too advanced, and thus they were restored to complete working order after capacitor replacement. CMOS batteries were also replaced in both, which is a very straightforward process unless the batteries have leaked their corrosive insides...

Below is a picture of some of the original capacitors on one of the boards, after a little bit of cleaning had already been done. Note the presence of liquid, and that some traces have corroded sections that have discolored. Note that even if a trace is discolored, it may still be fine, since it does take a fair while for a trace to dissolve all the way through. Nonetheless, once the original capacitors have been removed, the board should be cleaned thoroughly to remove any corrosive liquid remaining. In some cases as well, liquid had formed a paste in between pins of some of the chips, which was carefully scraped out with a small hobby knife. For cleaning, cotton swabs with isopropyl alcohol were used.

Various options exist as to the types of capacitors that are able to replace the surface-mount aluminum electrolytic type originally used. While traditional electrolytic capacitors remain the cheapest, they are not recommended, since they have generally the shortest lifespan, and of course, since they can potentially leak all over again. Some recommend surface-mount tantalum capacitors, but these, like the electrolytics, have small and short leads that are difficult to solder, and are polarized.

The best type, in my opinion, is the MLCC—Multi-Layer Ceramic Capacitor. These are non-polarized, have very large and easily accessible solder pads, and no liquid electrolyte. The only drawback is that they tend to be relatively expensive, but the cost is still not very significant, at a maximum of a few CAD per capacitor. Interestingly, IIci motherboards do utilize some MLCCs from the factory, but only for lower capacitance values.

Both of my IIcis have the same revision of motherboard (820-0242-A), which utilizes the following surface-mount electrolytic caps:

  • 2x: 10µF 16V
  • 8x: 47µF 16V

Note that the above quantities are for a single motherboard. These can be replaced by the following parts (with their Mouser part numbers listed), which are what I used:

  • 10µF 16V MLCC — 810-C3225X7R1C106K
  • 47µF 16V MLCC — 81-GRM32ER61C476ME15

Since they were also leaking, I replaced the electrolytic caps on the two cache cards, each of which uses 2x 22µF capacitors, with one card using 35V and the other using 25V units. The following part was used to replace all four capacitors:

  • 22µF 35V MLCC — 810-C3216X5R1V226M

Below are two images of the replacement capacitors installed. The one on the right shows the small jumper wire that was added due to a lifted pad.

Desoldering the original electrolytics can be difficult, since most of the length of the leads are underneath the capacitor, unable to be touched with a soldering iron. In my opinion, it's a bad package design that is not made with ease-of-service in mind. Nonetheless, I found that tinning the iron's tip with a blob that would then be pressed to the exposed section of pad worked decently well, except for with the most corroded pads. In my case, only one pad in total was lifted (after doing both motherboards), requiring a small jumper wire to make the connection.

At the same time as replacing the surface-mount electrolytic caps, the axial-leaded units were also replaced. This was probably unnecessary, since the removed units tested fine, and of course, I have pieces of equipment more than 20 years older than the IIcis that still have properly functional electrolytics. So, unless they are leaking/bulging/etc., I wouldn't bother replacing them.

Anyway, if you have a Mac IIci or other vintage Mac, I would highly recommend checking yours to see if anything has started leaking (mostly the capacitors, but the CMOS battery should also be checked). If so, a short-term fix would be to clean up the liquid using cotton swabs soaked in isopropyl alcohol. Eventually though, they must be replaced, especially since the capacitors go out-of-spec as they leak. Of course, if you are lacking soldering and general electronics experience, I wouldn't recommend trying it yourself. There are people who can perform a recap for you for a reasonable cost.

Another thing that is recommended to check is the pins of the 68030 processor, making sure none are touching each other. These pins are very closely spaced and delicate, and can easily be shorted together (or close to it) by accident. One of the IIcis had two such shorts.

The Hardware

Below is an image taken with the top cover off, which typically can be removed simply by lifting the two clips at the back.

Where the IIcx has a 16 MHz 68030 CPU & 68882 FPU, the IIci brings this up to 25 MHz, with the same chip types, although a different CPU package—the IIcx has a PGA 68030, where the IIci has a smaller QFP package.

Originally, the IIci would have come with either a 40 or 80 MB hard drive. Mine both have larger drives; one has a 210 MB Quantum Prodrive 210S, while the other has a 2.1 GB Seagate Barracuda ST32550N.

As for RAM, the IIci originally came with 1 MB or 4 MB, but with remarkable upgradability. At max, the IIci can utilize a whopping 128MB of RAM. Consider for a moment... it's common for a modern computer to come with 1 GB - 4 GB of RAM, but to be upgradeable to 128 GB would be unbelievable! Depending on which machine I'm interested in using, I'll tend to install all of my eight RAM sticks into it, rather than keeping four in each machine, since they do have to be installed in groups of four.

Physically, the case is nearly identical to that of its predecessor, the IIcx. It is also very similar to that of the later Quadra 700, so much so that relplacing a IIci's motherboard with that of a Quadra 700 was an upgrade promoted by Apple.

It is easy and common to dismiss older computer hardware as being incapable of useful function in today's world. However, if such a machine is entirely functional—as it would have been when new—it virtually cannot be incapable of useful function (though it may not be the ideal choice for a given function), especially considering it was useful enough to be sold for considerable amounts of money to begin with. On the last point, the IIci's original list price was $6,269 USD (or $8,798, depending who you ask) in 1989! Yet, despite a massive decrease on average, people still complain about computer prices...

That is not to say, of course, that vintage machines like these are equivalent in function to modern machines; they are not. In the case of the IIci, having been introduced in 1989, it was produced before many people used the internet. Thus, even when significantly upgraded, it is quite poorly suited to uses involving such, although it is technically possible to view certain webpages using the machine. Certain things like word processing can be done much the same as on modern units, and it's often easier to run older Mac software on real hardware than to mess with virtual machines, plus you get to marvel at the beauty of the CRT monitor and the whirring of the SCSI hard drive. Not to mention that it has a floppy drive capable of reading Mac-formatted 400k and 800k double-density disks, which is something most modern USB floppy drives cannot do.

The Sounds

You may wonder what qualifies the IIci to be listed in the "Musical Computer" category. While it does not have built-in MIDI ports like the Atari 1040STfm, it does have built-in PCM audio capabilities, and can run a variety of programs for use in audio generation and processing. As for the PCM audio, while it is stereo, the maximum sample rate of the output appears to be 22.255 kHz, and with an 8-bit sample width, so it is hardly "hi-fi". (For reference, the CD standard is 44.1 kHz and 16-bit.) The IIci only contains a single internal speaker, so the 1/8" stereo jack in the back must be used in order to take advantage of the stereo capability.

As for audio software, one example is Macromedia SoundEdit 16 Ver. 2, which was released in 1996. This software is able to generate tones, including some basic FM, and it has many effects that can be applied to the sounds. It reminds me greatly of the more recent "Audacity".


Capacitor Replacement - 68kMLA Wiki - More info on capacitor replacement

The Macintosh IIci Site - Website dedicated to the Mac IIci, with a large amount of info.

Macintosh IIci Specs @ - Detailed specifications of the IIci

Macintosh IIci - Wikipedia, the free encyclopedia - More info on the IIci

If you notice any errors or have additional information that you would like to add, please contact me!

Last Updated: 6/29/2016