How much revenue has the x86 line of processors generated for Intel over the years? My best estimate is in 2023 dollars it’s at least $1 trillion by now. How many products, in any industry, that have come anywhere near this level of sales over a period of more than forty years?
The great irony, of course, is that the first CPU in the x86 line, the 8086, was never intended to last more than a few years. It was explicitly a ‘stop-gap’.
In 1975 Intel was putting its weight behind the 8800, a design that would become the iAPX432. The story of the iAPX432 is for another post, but it’s enough to say that it was wildly ambitious and repeatedly delayed.
So as early as 1976, it was clear that Intel would need a simpler design that would compete with the first generation of 16-bit microprocessors from rivals such as Motorola and Zilog.
The task of designing the Instruction Set Architecture for the 8086 was given to software engineer Stephen Morse. He was given very few constraints: it had to be possible to convert 8-bit Intel 8080 / 8085 assembly language to work on the new processor and it had to address at least 128k memory. Morse, working with project manager Bill Pohlman, started work on the 8086 in May 1976.