Cray 2

Cray-2

Cray-2 central unit (foreground) and Fluorinert-cooling "waterfall" (background), on display at the EPFL.
Manufacturer	Cray Research
Type	Supercomputer
Release date	1985 (1985)
Discontinued	1990
Predecessor	Cray X-MP

The Cray-2 is a supercomputer with four vector processors made by Cray Research starting in 1985. At 1.9 GFLOPS peak performance, it was the fastest machine in the world when it was released, replacing the Cray X-MP in that spot. It was, in turn, replaced in that spot by the Cray Y-MP in 1988.

The Cray-2 was the first of Seymour Cray's designs to successfully use multiple CPUs. This had been attempted in the CDC 8600 in the early 1970s, but the emitter-coupled logic (ECL) transistors of the era were too difficult to package into a working machine. The Cray-2 addressed this through the use of ECL integrated circuits, packing them in a novel 3D wiring that greatly increased circuit density.

The dense packaging and resulting heat loads were a major problem for the Cray-2. This was solved in a unique fashion by forcing the electrically inert Fluorinert liquid through the circuitry under pressure and then cooling it outside the processor box. The unique "waterfall" cooler system came to represent high-performance computing in the public eye and was found in many informational films and as a movie prop for some time.

Unlike the original Cray-1, the Cray-2 had difficulties delivering peak performance. Other machines from the company, like the X-MP and Y-MP, outsold the Cray-2 by a wide margin. When Cray began development of the Cray-3, the company chose to develop the Cray C90 series instead. This is the same sequence of events that occurred when the 8600 was being developed, and as in that case, Cray left the company.

With the successful launch of his famed Cray-1, Seymour Cray turned to the design of its successor. By 1979 he had become fed up with management interruptions in what was now a large company, and as he had done in the past, decided to resign his management post and move to form a new lab. As with his original move to Chippewa Falls, Wisconsin from Control Data HQ in Minneapolis, Minnesota, Cray management understood his needs and supported his move to a new lab in Boulder, Colorado. Working as an independent consultant at these new Cray Labs, starting in 1980 he put together a team and started on a completely new design. This Lab would later close, and a decade later a new facility in Colorado Springs would open.