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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.

It's much easier to build circuits with standard cells. Instead of manually arranging each transistor, you feed a description of the logic into a computer. It places the cells into rows, and then routes the wires to connect the cells. In 1985, this took many hours on an IBM mainframe computer.

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!