A.I.
Hardware · Data center
Fairwater
Fairwater is Microsoft's design for AI data centers that work as one giant computer. The first site is in Mount Pleasant, Wisconsin (Microsoft, 18 Sep 2025). The second, in Atlanta, Georgia, was unveiled on 12 November 2025 and is linked to Wisconsin by a dedicated network Microsoft calls the AI WAN, making what it calls an AI superfactory (Microsoft, 12 Nov 2025).
Key figures
| Figure | Fairwater |
|---|---|
| Wisconsin site | 315 acres, 3 buildings, 1.2 million sq ft |
| Chips | Hundreds of thousands of Nvidia GB200 and GB300 GPUs |
| Per rack | Up to 72 Blackwell GPUs, 1.8 TB/s GPU-to-GPU, over 14 TB pooled memory |
| Rack power | About 140 kW per rack, 1,360 kW per row |
| Network between racks | 800 Gb/s GPU to GPU, two-tier Ethernet |
| Fiber laid | Over 120,000 new miles across the US |
A GPU, or graphics processing unit, is the chip that does most AI math. kW is a thousand watts. Gb/s is gigabits per second.
Cooling and building
Fairwater uses closed-loop liquid cooling: the water is filled once and reused, which Microsoft says equals what 20 homes use in a year and is designed to last 6+ years. Heat goes to one of the largest chiller plants in the world. Buildings are two stories so racks can sit above and below each other, which shortens cables.
Power
Microsoft says the Atlanta site was picked for very reliable grid power, so it skips on-site generators and UPS (battery backup) for the GPUs.
What Microsoft claims
- Microsoft called Wisconsin the world's most powerful AI datacenter and said it would deliver 10 times the performance of today's fastest supercomputer. These are Microsoft's own claims.