Ah, the Zip Chip. For those unfamiliar, the Zip Chip was a popular CPU accelerator solution for the Apple II series of machines, which bumped the default 1MHz CPU speed anywhere from 4MHz to 8MHz depending on the upgrade chip model. These chips are understandably still in demand and devilishly difficult to source. Unfortunately, when one does run across one of these treasures, it may turn out not to be what you’d bargained for.
I’ve come across a couple of these on eBay, and actually wound up buying a “phony” one last month (the other was also a phony, but the auction was more transparent to that fact). To be clear though, it wasn’t intentionally sold to deceive. Likely, the scenario played out along these lines:
Twenty years ago, an Apple IIe owner buys a new Zip Chip. He installs the chip in his Apple IIe and removes the old 1MHz CPU, placing it in the same foam block the Zip Chip was housed in for safekeeping. He then places the old 1MHz CPU, manual, and diskette back in the original Zip box and stores it on the shelf. (Same thing I would have done.)
Over the years, the Apple IIe is sold, passed on or otherwise disposed of with the Zip Chip still installed. The original Zip Chip box finds its way to another owner, probably mixed in with other Apple II software, and is placed on eBay. Hey, it’s got a CPU in the box - it must be complete!
Gullible individual (me) buys it, finding a bog standard 1MHz CPU (a Rockwell 65C02 338-6503 pulled from a stock IIe).
In closing, make absolutely certain the Zip Chip in a given box is the real thing - there’s a very high probability it contains nothing more than leftovers from a previous upgrade. It’s becoming more and more apparent that the best way to get a Zip Chip is to find an Apple II with one already installed.