NCAR Cray-1A S/N 3

Also known as Cray-1A serial 3; C1

Operated by NCAR at NCAR Mesa Laboratory (Boulder) .

Phase 1 seed dataset, compiled by hand. These rows were built from public operator, laboratory and vendor sources. A mechanical second-reader pass has since fetched every cited source: 1263 of 1345 systems have a readable citation that names them, and 56 are genuinely weakly sourced. Every claim carries its source and a confidence tier. Treat anything below verified as a lead, not a citation.

Measured performance

Rmax: -
Rpeak: 0.2 GFlop/s
Rmax ÷ Rpeak: -
Cores: 1
Power: 115 kW
Per watt: - GF/W

Figures are as last publicly reported for the configuration described below, not a live measurement. Where a system was upgraded in place, the post-upgrade configuration is shown and the earlier one appears in the timeline.

What this machine is made of

One row per supplier relationship. “Supplier at build” is the company that shipped the part at the time; where that company has since been acquired, the parent it rolls up to today is shown beside it. That distinction is what makes ticker-level aggregation possible across a thirty-year dataset.

Role	Part	Supplier at build	Quantity	Confidence	Source
Integrator	- Cray Research, Inc. Cray-1A serial number 3	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	cisl.ucar.edu
CPU	Cray-1 CPU CPUs Cray-1 (custom) · 1C · 0.08 GHz Cray-1A single vector processor, 12.5 ns clock	Cray HPENYSE rolls up to Hewlett Packard Enterprise	1 reported	Reported	cisl.ucar.edu en.wikipedia.org
Operating system	- Cray Operating System (COS) with Cray Fortran Translator	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	cisl.ucar.edu

The read

Serial number 3 arrived at NCAR on 11 July 1977 for $8.86 million (about $7.9 million for the system plus nearly $1 million for disks), after the first Cray-1 had gone to Los Alamos for a six-month trial in 1976. NCAR says it was Cray Research's first official customer and that accepting this machine in December 1977 made Cray Research revenue-generating; it was the first Cray-1A to go into production. NCAR describes a 12.5 ns clock, eight 64-element vector registers, 1 million 64-bit words (8 MB) of memory, 16 DD-19 disk drives of 300 MB each and a peak of 160 MFLOPS. It drew about 115 kW, ran with the CDC 7600 as front end, and was removed from production on 27 January 1989 and powered off on 1 February after nearly 12 years, NCAR's longest-lived supercomputer. Wikipedia repeats NCAR's estimate of 4.5 times the throughput of the 7600. NCAR is the primary source for the dates, so the tier is reported.

Timeline

1975 Announced source
1977-07 First operational source
1989-02 Decommissioned source

Site & facility

NCAR Mesa Laboratory (Boulder)

Location: Boulder, CO, USA
Commissioned: 1986

cisl.ucar.edu cisl.ucar.edu

Change history

2026-10-09 Added NCAR Cray-1A S/N 3

Source check

We fetched this system's own citations and recorded whether each page actually mentions it. This is a corroboration signal, not a fact check, and it is published so you can see how well the sourcing holds up rather than take it on trust.

Cited source	Result	Found on the page
en.wikipedia.org	names system, part and count	Cray-1 CPU · counts: 1
cisl.ucar.edu	names system, part and count	Cray-1 CPU · counts: 1

Checked 2026-10-13 by pnpm verify. Re-run it and the table changes with the web.