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Intel's 386 processor (1985) was critical to the success of Intel. With 285,000 transistors, it was too much for Intel's design process and the schedule started slipping. Intel pivoted to "standard cells", an automated technique for chip layout to get back on track. Let's look closer...

The previous photo shows the 386 processor under a microscope. I've highlighted the regions that use standard cells and the layout was automated. Simple logic blocks (the "standard cells") are arranged in rows, with wiring between the rows. This creates a distinctive striped pattern.

In standard cell logic, all the transistors are in orderly stripes. Except one that's out of place below, in the middle of the wiring region. What's going on? I think it's a bug fix. Instead of redoing all the circuitry, someone realized they could patch an extra transistor into an empty spot!

Standard cells sped up the design of the 386 and the chip was completed ahead of schedule. Pat Gelsinger was one of the key people behind the use of standard cells in the 386 processor. Decades later, he became CEO of Intel.