Flex and Cerebras Expand Partnership to Increase U.S. Factory Capacity

Flex and Cerebras Systems Inc. announced today the expansion of their manufacturing partnership, increasing production of the Cerebras CS-3 system at Flex’s facility in Milpitas, California—the world’s most advanced AI accelerator system. As demand for AI infrastructure accelerates, this collaboration marks a significant expansion of U.S. advanced manufacturing capabilities.

By adding production lines, expanding factory space, deploying advanced testing infrastructure, and increasing the number of skilled local manufacturing professionals in California, the planned expansion is expected to boost CS-3’s production capacity by approximately sevenfold by 2026. In an era where electronics manufacturing is often linked to overseas supply chains, this collaboration demonstrates that the world’s most sophisticated AI systems are being designed, assembled, integrated, and tested in the heart of Silicon Valley.

Dhiraj Mallick, Chief Operating Officer of Cerebras, stated: “The CS-3 differs from any previous computer system, and scaling its production requires an exceptional manufacturing partner. Flex brings the technical depth, operational rigor, and manufacturing expertise needed to support this scale. While it is often assumed that the entire AI manufacturing and packaging supply chain is overseas, teams of American engineers and technicians are building world-leading AI systems across the country every day, powering cutting-edge AI workloads globally.”

The CS-3 is based on Cerebras’ industry-leading wafer-scale engine architecture, with a processor physical size larger than any traditional AI chip. This system integrates advanced liquid cooling, high-density power delivery, precision mechanical assembly, and tightly coordinated network infrastructure into a single platform, specifically designed for large-scale AI training and inference.

Manufacturing the CS-3 presents rare challenges in traditional server production. Each system requires specialized handling processes, custom tooling, precise calibration, and extensive system-level validation. Flex engineers collaborated closely with Cerebras to develop assembly processes, automated test stations, and novel manufacturing methods specifically tailored for wafer-scale computing systems.

Rob Campbell, President of Flex Communications, Enterprise, and Cloud Business, stated: “The CS-3 is entirely different from traditional server or rack-level computing platforms. Every manufacturing stage, from mechanical integration to thermal validation and final system qualification, requires deep collaboration among our engineering teams. We appreciate Cerebras’ partnership, demonstrating the heights achievable in advanced U.S. manufacturing when two highly technical organizations work side by side.”

To support production capacity expansion, Flex is expanding its dedicated manufacturing operations in Milpitas for Cerebras, with multiple new assembly and integration production lines set to commence operations in 2026. As production accelerates to meet the demands of AI model developers, cloud service providers, and enterprise customers, the factory space dedicated to CS-3 manufacturing is expected to significantly increase this year.