Supercomputers/Systems/HPCx
United Kingdom · decommissioned · hpc
HPCx
Also known as HPCx Phase 1
Operated by EPCC .
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
- 3.24 TFlop/s
- Rpeak
- 6.66 TFlop/s
- Rmax ÷ Rpeak
- 48.7%
- Cores
- 1,280
- 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 eServer p690 (pSeries 690 Turbo) | IBM | - | Reported | top500.orgen.wikipedia.org |
| CPU | - IBM POWER4 1.3 GHz | IBM | 1,280 reported | Reported | top500.orgen.wikipedia.org |
| Interconnect | - IBM Colony switch | IBM | - | Reported | top500.orgen.wikipedia.org |
| Operating system | IBM AIX Operating systems Unix (System V-derived) · Proprietary AIX | IBM | - | Reported | top500.org |
The read
The UK's national academic supercomputer from December 2002, run by a consortium led by EPCC at the University of Edinburgh with the Science and Technology Facilities Council and IBM. Phase 1 was 1,280 POWER4 processors in IBM p690 nodes on the Colony switch with 1.28 TB of memory and about 6.6 TFlop/s peak; it was expanded in later phases and the service ended in January 2010, after HECToR took over from 2007. TOP500 ranked this entry ninth on the November 2002 list at 3,241 GFlop/s Rmax. Wikipedia is inconsistent about where the machine sat (Daresbury or Edinburgh), so no site is linked. TOP500 is the only source for Rmax, so the tier is reported.
Timeline
- 2002-11 List debut at #9 (November 2002) source
- 2002-12 First operational source
- 2010-01 Decommissioned source
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Change history
- 2026-10-02 Added HPCx, the UK national IBM p690 system, ninth on the November 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 |
|---|---|---|
| en.wikipedia.org | names system only | - |
| top500.org | names system only | - |
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.