Supercomputers/Systems/Tohoku SX-4/128H4
Japan · operational · hpc
Tohoku SX-4/128H4
Also known as NEC SX-4/128H4 at Tohoku University
Operated by Cyberscience Center, Tohoku University at Tohoku University Cyberscience Center .
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
- 244.0 GFlop/s
- Rpeak
- 256.0 GFlop/s
- Rmax ÷ Rpeak
- 95.3%
- Cores
- 128
- 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 | - NEC built the SX-4/128H4 | NEC | - | Reported | cc.tohoku.ac.jptop500.org |
| CPU | - NEC SX-4 vector processors, 128 CPUs | NEC | 128 reported | Reported | top500.org |
The read
NEC SX-4/128H4 vector supercomputer at Tohoku University's computing centre (today the Cyberscience Center). The centre's history page records the SX-4/128H4 entering operation in January 1998 and the SX-7 following in January 2003. TOP500 lists 128 cores at 256 GFlop/s Rpeak and 244 GFlop/s Rmax on a multi-stage crossbar under EWS-UX/V, 13th on the June 1998 list and last at rank 490 in June 2003; its page gives 1997 as the installation year (https://www.top500.org/system/170820/). Tohoku's page gives no shutdown date, so status is recorded as of the last list appearance. 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
- 2026-10-09 Added Tohoku SX-4/128H4
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 |
|---|---|---|
| cc.tohoku.ac.jp | 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.