Seymour Cray

Seymour Cray: The Wizard of Chippewa Falls

When a manager once asked Seymour Cray for a five-year plan, he handed back a single line: “Five-year goal: Build the biggest computer in the world. One year goal: One-fifth of the above.” That was the whole philosophy of the man who invented the supercomputer. He designed on quarter-inch quadrille pads, worked from a lab in a small Wisconsin town, dug tunnels under his house for inspiration, and for three decades built the fastest computers on earth — machines that ran the world’s weather models and nuclear weapons codes. Larry Smarr called him “the Thomas Edison of the supercomputing industry.”

A Basement Laboratory

Seymour Roger Cray was born on 28 September 1925 in Chippewa Falls, Wisconsin, the son of a civil engineer who encouraged his experiments. By ten he had built a device from Erector Set parts that converted punched paper tape into Morse code, and the family basement became his laboratory. Drafted in 1943, he served in World War II as a radio operator, seeing combat in Europe and then helping break Japanese naval codes in the Pacific. He returned to take a B.Sc. in electrical engineering from the University of Minnesota in 1949 and a master’s in applied mathematics in 1951.

From Codebreakers to Control Data

In 1950 Cray joined Engineering Research Associates, a firm grown from a Navy codebreaking laboratory, where he worked on the ERA 1103, the first commercially successful scientific computer. When the company was swallowed by Sperry, a dissatisfied Cray joined William Norris in 1957 to found Control Data Corporation. By 1960 he had delivered the CDC 1604, a faster and cheaper machine that established his reputation.

Inventing the Supercomputer

His breakthrough was the CDC 6600 of 1964, the first commercial supercomputer, which crushed all rivals including IBM’s Stretch. Cray’s insight was that raw processor speed was not enough: “the trick is to build a fast system,” he said, and he devoted attention to input/output bandwidth so the processor was never starved of data, using peripheral processors to handle the traffic. The follow-up CDC 7600 was five times faster again — and, in a Cray touch, dressed in blue-glass doors and walnut trim, because he thought design was part of engineering.

Cray Research

Frustrated by corporate interruptions, Cray had already moved his work to a lab on his own land in Chippewa Falls, complete with a bomb shelter. After CDC declined to fully fund his CDC 8600, he left, and in 1973 founded Cray Research with Norris’s backing. The Cray-1, released in 1976, was both a computing landmark and a design icon: a C-shaped tower wrapped in a padded bench, cooled by refrigerant channels cast into its frame. Serial number 001 went to Los Alamos; the first commercial sale, to the National Center for Atmospheric Research, fetched $8.8 million. More than eighty were sold, and Cray became “The Wizard of Chippewa Falls.”

The Craftsman’s Method

Cray’s engineering rested on two obsessions: removing heat and controlling timing. He built elaborate cooling systems and interlocks that would not let a machine run without them. He hand-tuned the lengths of circuit-board traces so that signals meant to arrive together did arrive together, routing wires back and forth and applying Maxwell’s equations to account for radio-frequency effects. Asked about computer-aided design tools, he said he preferred faintly-ruled quarter-inch quadrille paper.

Why Seymour Is Called a Genius

Cray’s genius is technical and unambiguous, and it is worth naming precisely. It was systems-level engineering intuition of the highest order: the ability to hold an entire machine — logic, memory bandwidth, heat, and the physics of a signal traveling down a wire — in one mind at once, and to optimize all of it together. The Computer History Museum credits him with “staggering genius” that “resulted in the fastest computers on earth,” and industry figures like HP’s Joel Birnbaum said it was “impossible to exaggerate the effect he had on the industry.” Unlike many honored with the word, Cray earned it through repeated, quantifiable results: machine after machine that was, at launch, simply the fastest in the world. The honest counter-case is that his brilliance was also his limit. He famously resisted massively parallel computing — “if you were plowing a field, which would you rather use: two strong oxen or 1024 chickens?” — and his final gambles, the Cray-2 and especially the gallium-arsenide Cray-3, were commercial failures overtaken by the parallel architectures he distrusted; Cray Computer Corporation went bankrupt in 1995. His was the genius of the singular master craftsman, supreme within his paradigm and slow to abandon it. But within that paradigm he was unmatched, and he essentially created an entire industry.

Legacy

On 5 October 1996, Cray died from injuries suffered in a car crash near Colorado Springs, a week after his seventy-first birthday, while already designing a new parallel machine at his last venture, SRC Computers. The IEEE Computer Society created the Seymour Cray Computer Engineering Award in his honor the following year. His machines defined an era of science and defense, his design sense made computers beautiful, and his name still means one thing above all others: speed. He remains, without serious rival, the father of supercomputing.

Achievements

• National Inventors Hall of Fame — 1997
• Affiliated with Control Data Corporation and Cray
• Educated at University of Minnesota and Chippewa Falls High School
• Worked as engineer, computer scientist and electrical engineer