Microsoft confirmed June 23, 2026, that its Fairwater campus in Mount Pleasant, Wisconsin, is fully operational, linking hundreds of thousands of NVIDIA GB200 Blackwell GPUs into a single cluster using a two-story building design, 800-gigabit-per-second Ethernet fabric, and a proprietary networking protocol co-developed with OpenAI and NVIDIA. The $7.3 billion Wisconsin investment marks the fulfillment of a commitment Microsoft made in May 2024, when the company pledged $3.3 billion to build an AI campus on land in Racine County. Microsoft Source confirmed the campus reached full operational status after equipment came online in April and startup activities followed. Microsoft broke ground in 2023 and expanded the commitment to $7.3 billion in September 2025, adding a second facility now under active construction. About 10,000 construction workers built the first facility over roughly two years; approximately 550 full-time employees are currently on site. Each Fairwater building uses two stories of GPU racks with through-floor networking, and the two-level networking tree uses a protocol called Multi-Path Reliable Connected (MRC), described as a software-layer innovation on top of commodity Ethernet hardware.