Supercomputers/Systems/Seaborg
USA · decommissioned · hpc
Seaborg
Also known as NERSC IBM SP, SP Power3 375 MHz 16 way
Operated by Lawrence Berkeley National Laboratory at Oakland Scientific Facility .
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: 1092 of 1153 systems have a readable citation that names them, and 40 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
- 3.05 TFlop/s
- Rpeak
- 4.99 TFlop/s
- Rmax ÷ Rpeak
- 61.1%
- Cores
- 3,328
- Power
- -
- 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 | - IBM RS/6000 SP | IBM | - | Reported | top500.orgwww2.lbl.gov |
| CPU | IBM POWER3-II CPUs POWER · 1C · 0.375 GHz · 220 nm IBM POWER3 375 MHz | IBM | 3,328 reported | Reported | top500.orgwww2.lbl.gov |
| Interconnect | IBM SP Switch Interconnect multi-stage Omega network · 150 MB/s per node IBM SP Switch | IBM | - | Reported | top500.orgwww2.lbl.gov |
| Operating system | IBM AIX Operating systems Unix (System V-derived) · Proprietary AIX | IBM | - | Reported | top500.orgwww2.lbl.gov |
The read
NERSC's IBM RS/6000 SP, named for Glenn Seaborg, announced in October 2001 as the largest unclassified supercomputer with 3,328 processors and 5 TFlop/s peak at the Oakland Scientific Facility; Berkeley Lab says it later reached about 10 TFlop/s. TOP500 lists 3,328 POWER3 375 MHz cores on the SP Switch under AIX, fifth on the June 2002 list (3,052 GFlop/s Rmax in that list's table, where the system page shows 3,652), and an earlier 2,528-processor configuration second on the June 2001 list. The June 2002 edition is recorded here. No source we fetched gives a retirement date. TOP500 is the only source for Rmax, so the tier is reported.
Timeline
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Site & facility
Change history
- 2026-10-02 Added Seaborg, NERSC's IBM SP, fifth on the June 2002 TOP500
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 |
|---|---|---|
| top500.org | names system only | · counts: 3328 |
| www2.lbl.gov | names system only | · counts: 3328 |
Checked 2026-10-09 by pnpm verify. Re-run it and the table changes with the web.
Further reading
Inside a node
Latency-optimised versus throughput-optimised processors, NUMA, and the end of the host-to-device copy.
The interconnect
Topologies, why latency and tail behaviour matter more than bandwidth, and how the fabric market consolidated.
Programming a supercomputer
The software stack beneath the application, and why the OS is now a sovereignty signal as much as a technical choice.