The worst-selling Microsoft software product of all time: OS/2 for the Mach 20

In the mid-1980's, Microsoft produced an expansion card for the IBM PC and PC XT, known as the Mach 10. In addition to occupying an expansion slot, it also replaced your CPU: You unplugged your old and busted 4.77 MHz 8088 CPU and plugged into the now-empty socket a special adapter that led via a ribbon cable back to the Mach 10 card. On the Mach 10 card was the new hotness: A 9.54 MHz 8086 CPU. This gave you a 2* performance upgrade for a lot less money than an IBM PC AT. The Mach 10 also came with a mouse port, so you could add a mouse without having to burn an additional expansion slot.

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The Mach 20 took the same basic idea as the Mach 10, but to the next level: As before, you unplugged your old 4.77 MHz 8088 CPU and replaced it with an adapter that led via ribbon cable to the Mach 20 card, which you plugged into an expansion slot. This time, the Mach 20 had an 8 MHz 80286 CPU, so you were really cooking with gas now. And, like the Mach 10, it had a mouse port built in. According to a review in Info World, it retailed for $495.

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Microsoft also produced a customized version of OS/2 for the Mach 20. Despite being tailor-made for the Mach 20, it still had terrible performance problems.

One of my former colleagues spoke with the person who took over from him as the support specialist for OS/2 for Mach 20. According to that person's memory (which given the amount time that has elapsed, means that we should basically be saying according to legend" at this point), a total of eleven copies of OS/2 for Mach 20" were ever sold, and eight of them were returned.

That leaves three customers who purchased a copy and didn't return it. And the support specialist had personally spoken with two of them.

If these numbers are accurate, I believe this makes OS/2 for Mach 20 a strong candidate for being the worst-selling actually-shipped Microsoft software product of all time.

We have to find this. Someone must have a copy of OS/2 for Mach 20 in a box in the attic somewhere. This is the final boss of software preservation.