Serial Number 1

The first of a kind always holds special interest for historians and serial number one, the first Cray-1 computer system is no exception. Made in 1976 this machine, really just the prototype but proved it’s worth at 6 sites paving the way for early sales of Cray Research Supercomputers.

Cray-1 Serial Number 1
Serial Number 1 World Traveller From Cray Channels Magazine

In March 1976 the CRAY-1 Serial I was installed at the Los Alamos Scientific Laboratory (LASL). in Los Alamos. New Mexico. This marked the beginning of Serial 1’s extensive travels for diverse applications.
LASL is noted as being the site of the first CRAY-1 and the initial prototype testing. For six months following installation. Serial 1 underwent rigorous testing to verify workload speed and reliability demands. Performance threshold criteria were formally established in three areas: scalar-processing speed. vector processing speed and reliability. The CRAY-1 met or exceeded all performance criteria.
In September 1977 LASL replaced Serial I, a half-million word memory system, with the CRAY-1 Serial 4. a full million word memory system with automatic error correction. Thus Serial 1 left LASL to travel to the next customer in line the European Centre for Medium Range Weather Forecasts (ECMWF) based in Reading. UK. Serial 1 was shipped from CRI’s Hallie Lab (in Chippewa Falls. Wisconsin) via New York arriving in the U.K. during October. 1977.

ECMWF used Serial 1, was housed at the Rutherford National Laboratory until October 1978 when a full million word system was delivered to the Centre’s new headquarters in Reading. England. The delivery of this upgraded mainframe sent Serial 1 to a U.K. government customer who was awaiting delivery of a millionword system.  While visiting Daresbury, I was extremely impressed with the facilities and struck by the high level of interest and enthusiasm exhibited by the diverse staff. There is a strong esprit de corps among the Daresbury physicists. electronics and computer experts. engineers. technicians. craftsmen. and administrators. Central to this feeling is the knowledge that the work being done at the lab will help provide scientific advances in many fields. Scientists throughout the British Isles can access the Daresbury computer network. either directly at the lab or through any of a number of universities and research institutes. Thus the CRAY-1 at Daresbury is servicing a multitude of scientific disciplines. providing the computing capability necessary to support the links between the growing experimental programs and the theoretical studies.  After seeing this customer through the interim. Serial 1 was shipped to the north of England for the Science Research Council’s national laboratory at Daresbury (the feature topic of this issue of Channels).
Since June 1979. the Daresbury Lab has applied the CRAY-1 Serial 1 to its multi-faceted scientific environment. Disciplines benefiting from the availability of the Serial 1 include: protein crystallography. theoretical chemistry, atomic and molecular physics. oceanography. engineering. statistical mechanics and molecular dynamics. astrophysics, solid state physics,  plasma physics and nuclear theory.

After a spell at Daresbury SN1 went to to work at a couple of MOD sites before returning to Chippewa Falls in 1989.

{Slightly edited}

Where is SN1 Now

At the Chippewa Falls Museum of Industry and Technology More photos on link. See email confirmation below.



The travels continue

Serial 1 made a guest appearance at SC18 the Supercomputing conference in Dallas during 12-15 November 2018. Unboxing video here.


Curiously the nameplate lists the systems as a Cray-1B but as Serial S/N 1. Other records have SN19 as the only Cray-1B. Possibly a field upgrade was involved.

Machine SN1 at site Daresbury Lab

During it’s travels SN1 visited Daresbury in 1979. These pictures and text from the now missing page

The text for the original post can be seen here. The system in the pictures is described as a Cray-1S which is possibly incorrect as SN1 was a Cray-1A or B. The later Cray-1 SN28 delivered to Daresbury was a Cray-1s.






What happened to SN2?

Serial number 2 was scrapped after NCAR persuaded CRI that built in protection against memory errors was required. See about SECDED here.

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