Graywolf (NCAR Cray-3)

Also known as Cray-3 serial 5; CCC Cray-3 Graywolf

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: 4.0 GFlop/s
Rmax ÷ Rpeak: -
Cores: 4
Power: 90 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 Computer Corporation Cray-3 serial number 5, loaned to NCAR	Cray Computer Corporation	-	Reported	cisl.ucar.edu en.wikipedia.org
CPU	- Cray-3 gallium arsenide processors, 4 processors, 2.08 ns clock	Cray Computer Corporation	4 reported	Reported	cisl.ucar.edu
Cooling	- Circulating Fluorinert bath immersion cooling of the circuit modules	Cray Computer Corporation	-	Reported	cisl.ucar.edu
Operating system	- CSOS Colorado Springs Operating System, a port of Unix SVR4	Cray Computer Corporation	-	Reported	cisl.ucar.edu

The read

The Cray-3 was Seymour Cray's gallium-arsenide machine, built by Cray Computer Corporation (CCC), which Cray Research spun off in 1989. CCC delivered serial number 5, a two-octant, four-processor system with 128 megawords (1 GB) of memory and a 2.08 ns clock, to NCAR on 24 May 1993 as a loaned test and evaluation unit, and NCAR lists it in use from October 1993. It was immersed in circulating Fluorinert, drew about 90 kW, ran CCC's Unix SVR4-based CSOS and was linked by HIPPI to NCAR's mass storage. NCAR's atmospheric model exposed a square-root hardware error that CCC then fixed. NCAR's table gives 4 GFLOPS peak. Graywolf was decommissioned on 26 March 1995, the day after CCC filed Chapter 11, and returned to Colorado Springs. Wikipedia independently confirms the loan to NCAR and the bankruptcy. The tier is reported.

Timeline

1993-10 First operational source
1995-03 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 Graywolf (NCAR Cray-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 only	-
cisl.ucar.edu	names system only	-

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