Overview
NSF's Leadership System Runs in a Round Rock Colocation Hall
NSF set the LCCF budget at $457M in July 2024 under award 2323116; the figure covers hardware, operations and facility rental from Sabey. TACC picked Sabey's Round Rock campus as its colocation partner in August 2024.
Installation began in 2025, and in 2026 TACC opened early operations to large-scale Leadership Resource Allocation Committee (LRAC) projects; smaller and startup allocations follow later. Horizon replaces Frontera as TACC's leadership system, and 11 Characteristic Science Applications projects are lined up as first users.
| Operator | TACC, UT Austin |
|---|---|
| Funder | NSF, award 2323116 |
| Budget | $457M |
| Host | Sabey Data Centers, SDC Austin |
| Address | 1300 Louis Henna Blvd, Round Rock |
| Builders | Dell, NVIDIA, VAST Data |
| Other partners | Spectra Logic, Versity |
| Status | Early operations, 2026 |
| Predecessor | Frontera |
System
Grace Blackwell GPUs and Vera CPUs at 300 Petaflops
Horizon pairs about 4,000 NVIDIA Blackwell GPUs on Grace Blackwell nodes with NVIDIA Vera CPU servers, about 1 million CPU cores in all, on Dell PowerEdge servers in liquid-cooled racks. NVIDIA Quantum-2 InfiniBand links the nodes.
TACC rates Horizon at 300 petaflops for simulation, about 10 times Frontera, and at 20 exaflops bf16 and 80 exaflops FP4 for AI work. Early planning had cited 400 petaflops. VAST Data supplies 400 PB of all-flash storage at more than 10 TB/s, and the Ranch archive, the first LCCF system in production, holds more than one exabyte.
The research load spans climate and weather, materials, molecular dynamics, astrophysics and AI model training for open science, with 10,000 to 15,000 users expected each year.
Campus
Sabey Builds SDC Austin to 84 MW Across Two Buildings
Sabey, based in Seattle, demolished the former Sears Teleserv building at 1300 Louis Henna Boulevard and committed at least $185M in property improvements and $5M in equipment under a 2022 Round Rock incentive agreement. Building A opened in October 2024; Horizon runs in a 15 to 20 MW liquid-cooled data center on the campus.
Building B (Austin B), a three-story building with 54 MW of design capacity, started construction in 2025; its first 18 MW is due in the third quarter of 2027. At full buildout the campus reaches about 84 MW of critical IT load across more than 430,000 square feet. Dell Technologies headquarters is also in Round Rock.
Round Rock
Sabey, Switch and Skybox Anchor Round Rock's Data Centers
Skybox's site covers just under 30 acres east of A.W. Grimes Boulevard and south of Old Settlers Boulevard; the council approved it unanimously after hours of public comment. Larger Williamson County campuses sit east along US 79; see US 79 data center corridor and Skybox Prologis Hutto. Grid hookups for all of them run through ERCOT (the Electric Reliability Council of Texas) large-load rules set by Texas SB 6 (2025); see ERCOT large-load interconnection.
| Campus | Operator | Size | Status |
|---|---|---|---|
| SDC Austin (Horizon) | Sabey Data Centers | About 84 MW at buildout | Building A open; Building B due 2027 |
| The Rock, 300 Dell Way | Switch | Multi-building campus | Operating |
| Switch second building | Switch | 72,600 sq ft, up to $20M | Construction from mid-2026; done mid-2028 |
| Skybox Round Rock | Skybox Datacenters | 75 MW, up to 250,000 sq ft | Zoning approved Feb 12, 2026 |
Record
Dataset Record
- Sources
- Texas Advanced Computing Center, NSF, The Next Platform, HPCwire, VAST Data, Sabey Data Centers, DatacenterDynamics, City of Round Rock, Community Impact
- Last verified
- October 2026