Computer pioneer Gene Amdahl dies, aged 92

Gene Amdahl was responsible for fundamental work in computer architecture and design, the chief architect of the IBM System/360 and founder of mainframe maker Amdahl

Computer pioneer and entrepreneur Gene Amdahl has died, aged 92. Amdahl joined IBM in 1952 after graduating with a clutch of degrees from South Dakota State University and the University of Wisconsin.

As chief architect of the IBM 704 scientific mainframe computer, his engineering decisions helped IBM to sell many more of the machines than IBM had expected.

Amdahl left IBM in 1956, but rejoined in 1960 when he was appointed chief architect of the wildly popular System/360 series of mainframe computers - "a daring business and technical gamble that became one of the greatest success stories in the history of computing", according to the Computer History Museum.

Gene Amdahl founded his own, eponymously named company in 1970 after leaving IBM for a second time.

Amdahl Corporation's mainframes were designed to be IBM-compatible - capable of running the same software - but at lower cost. At its peak, it was one of the biggest computer makers in the world, with a global market share of about eight per cent of the mainframe market at a time when "national champion" computer makers were often protected by governments. It was, however, acquired by Fujitsu in 1997.

However, Gene Amdahl had left the mainframe company that he founded in 1979 and, in the 1980s, founded a number of other companies, none of which could approach the success of Amdahl Corporation. These start-ups include Trilogy Systems in 1979, which designed integrated chips for mainframes, and VLSI [very-large-scale integration] technology; and Andor International in 1987, which was intended to build mid-sized mainframes. That company also foundered.

Gene Amdahl was also the co-founder of Commercial Data Servers, in 1996, which developed mainframe-like machines with super-cooled microprocessors. It continues to trade today as Xbridge Systems, but in a very different form.

Gene Amdahl's degrees included a BS in engineering physics in 1948 from South Dakota University, and a Masters and a PhD in theoretical physics from the University of Wisconsin. He was named an IBM Fellow in 1965 and became a member of the US National Academy of Engineering in 1967. He was recognised as a "Centennial Alumnus" of South Dakota State University in 1986.

His 1951 PhD thesis, 'The Logical Design of an Intermediate Speed Digital Computer', can be read here.