In the 1970's I worked at a company that tried to put all that circuitry onto a silicon chip. Took Intel many years, a sequential process of size, features, power/cooling, equipment technology, etc, etc. Exactly how many depends on who one asks. Late 70's were very exciting. i8080 was reported to be the 1st commercially available microprocessor on a chip. It was either the end of 1977 or early '78, when the processor went into the Finished Goods Final Inventory. My desk, specifically, and under a double lock and key.