USA · decommissioned · hpc

Lonestar 4

Also known as TACC Lonestar 4

Operated by Texas Advanced Computing Center at Texas Advanced Computing 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: 251.80 TFlop/s
Rpeak: 301.78 TFlop/s
Rmax ÷ Rpeak: 83.4%
Cores: 22,656
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	- Dell PowerEdge M610 cluster	Dell Technologies DELLNYSE	-	Reported	top500.org datacenterknowledge.com
CPU	- Xeon X5680 6C 3.33GHz (Westmere)	Intel INTCNASDAQ	-	Reported	top500.org datacenterknowledge.com
Interconnect	Mellanox InfiniBand QDR Interconnect Fat tree · 40 Gb/s per 4x port Infiniband QDR (Mellanox 40Gb/s)	NVIDIA NVDANASDAQ	-	Reported	top500.org datacenterknowledge.com

The read

TACC's Dell PowerEdge M610 blade cluster for the NSF TeraGrid, University of Texas System, Texas A&M and Texas Tech, 39th on the November 2011 TOP500. TOP500 lists 22,656 Xeon X5680 6-core 3.33 GHz cores on InfiniBand QDR at 251.8 TFlop/s Rmax and 301.78 TFlop/s Rpeak, with list positions from 28th in June 2011 to 404th in November 2015. Data Center Knowledge's report independently confirms the TACC site, 1,888 Dell M610 blades with dual six-core Westmere processors, 302 teraflops peak, 44.3 TB of memory and Mellanox 40 Gb/s InfiniBand. Decommissioned reflects its disappearance from TOP500 after November 2015 after Lonestar 5 debuted on the November 2015 list; no retirement date is recorded. TOP500 is the only source for Rmax, so the tier is reported.

Timeline

2011 First operational source
2011-11 List debut at #39 (November 2011) source

Public list appearances

Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.

#39: TOP500, November 2011 →

Site & facility

Texas Advanced Computing Center

Location: Austin, TX, USA
Cooling: Direct liquid cooling
Commissioned: 2007

tacc.utexas.edu

Change history

2026-10-02 Added Lonestar 4, TACC's Dell blade cluster, 39th on the November 2011 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 and part	Mellanox InfiniBand QDR
datacenterknowledge.com	names system and part	Mellanox InfiniBand QDR

Checked 2026-10-09 by pnpm verify. Re-run it and the table changes with the web.