A Quadra Prototype in IIcx Clothing

I’m in a fortunate position running the Vintage Mac Museum in that I get offered the chance to acquire lots of old Macintosh equipment. Many of these items I already have, or can’t accept due to space constraints (the bane of every collector). But every so often an email arrives which piques my interest:

Quadra-PrototypeI just got in what I believe to be a Macintosh IIcx prototype. It is in a standard IIcx case with no markings on the front except the colored Apple logo. It has an unusual motherboard with 36MB RAM. The machine boots and operates with a Quantum APS Hard Drive with OS 7.5.5 installed. The bottom of the back case where everything plugs in is labelled metal and there is a sticker on the back that says Property of Apple Computer. Are you interested in it?

Why yes, now that you ask. Yes. I am interested!

I picked up the system and it is indeed unusual. The case has moldings on the back indicating it was for a IIcx, and there is no model name silk-screened on the front. There is a metal strip on the back for the ports with a space marked E’NET; the IIcx did not have built-in ethernet, you needed to use a NuBus card.


Similarly odd was the CPU, marked Motorola PC68040RC-A. The 68040 wasn’t used in the Mac II series, those debuted with the Quadra models. And that’s a strange nomenclature, the chip is normally identified as MC68040. Turns out what we have is actually a prototype 68040 CPU, the prefix PC being used to designate pre-production engineering samples.

Motorola-PC68040RC-AWell then, let’s review the evidence: a non-finished case, non-standard motherboard, prototype 68040 CPU, and a Property of Apple Computer sticker on the back. I think we’ve found a rather unique item here – A Wolf (Quadra) in Sheep’s (IIcx) Clothing.

However this may not be a Quadra prototype but rather a one-off custom creation. Upon further inspection I looked up the part number on the logic board, 820-0380-A, and it turns out to be a Quadra 650 logic board. That’s not a prototype part, and is newer than the first Quadra which was the model 700. Maybe this is some kind of Poor Man’s Quadra built by an Apple engineer with spare parts in the lab?

In any event it’s unusual, and makes a nice addition to the collection. The machine runs, though strangely the onboard AAUI ethernet port is not present and instead is supplemented by an Asante NuBus ethernet card. Sadly the Property of Apple Computer sticker was damaged before shipping and did not survive, but I have the photos from the previous owner. (Long story. Don’t ask.)

Who know what other strange beasts lurk in the bowels of Apple – or the garages of ex-Apple engineers…

4 responses to “A Quadra Prototype in IIcx Clothing”

  1. Pam Upchurch says:

    I’m inspired to make this iLamp! It’s so sleek and beautiful.

    My iMac Flat Panel dome is completely gutted and the screen is removed.
    My question is:
    How do I get the 3 wires out of the swivel arm? After using vise grips the 3 wires broke off flush. I’m assuming the new lamp wiring is threaded thru the swivel arm as I don’t see any loose lamp wiring in your well composed photos.

    My old flat panel was layed to rest in my closet because I couldn’t part with it and now I am thrilled to give her new life and a purpose!


  2. Shawn Hamachek says:

    Cool proto! Ran into this blog by accident. I happen to own four IIcx protos and documented the changes to each. Granted yours is a Quadra, not a IIcx. But I love old 68k protos. My oldest IIcx’s mainboard is called Avanti and the ROMS are called Three Stooges. The other three boxes are closer to production runs with main variations being case design. As I am sure you know, the IIcx was Apple first in house Mac II series design. Anyway, cool find and thanks for sharing!

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