Ohio's Prometheus AI Supercluster Set to Revolutionize AI Training with 1 Million GPUs

October 19, 2026
Ohio's Prometheus AI Supercluster Set to Revolutionize AI Training with 1 Million GPUs
  • Prometheus features dedicated FPGA-like fabrics for building-level Ethernet and a Backend Aggregation network spanning 2 km to over 100 km, using Arista switches and Broadcom Jericho3 silicon to optimize GPU-to-GPU communication.

  • Networking design for AI workloads centers on a dedicated BE network and a hierarchical data-center fabric, connecting regions from short hops to long-haul links to minimize training slowdowns.

  • Prometheus uses three generations of racks—Catalina with GB200 NVL72, Clemente with GB300 NVL72, and Vera Rubin NVL72 on San Miguel—that progressively increase memory, compute, and power efficiency per rack.

  • Power and cooling are managed with Dynamo Dimmer power control, synchronized training power transients, and a mix of air-assisted liquid cooling and facility liquid cooling, with renewable energy use and IcePack-inspired Open Compute designs shared.

  • Dynamo Dimmer enables intelligent power capping, battery storage, and liquid cooling to sustain high-density training while mitigating electrical limits.

  • Energy sustainability includes coolant efficiency, utilities collaboration, and ongoing work with renewables to support large-scale training.

  • Future roadmap envisions expanding Prometheus with Vera Rubin GPUs, integrating next-gen hardware into the fabric, and applying Prometheus insights to Hyperion in Louisiana with similar cooling and grid-connected designs.

  • San Miguel platform will feature 72 Vera Rubin GPUs per rack, high HBM4 memory and very high FP4/FP8 compute, paired with full liquid cooling; Hyperion will be Meta’s next 5 GW-scale supercluster in Louisiana with closed-loop cooling and direct grid connectivity.

  • Prometheus delivers high efficiency, with over 85% goodput in pre-training and more than 90% in reinforcement learning runs for Muse Wonder.

  • Vytautas Valinskas authored the piece, drawing on Meta’s public engineering blog and related sources for Muse Spark Open and Muse Wonder pricing.

  • Prometheus serves as a template for future efforts, with Hyperion planned as a larger follow-on and continued model releases aligned with hardware expansion.

  • Operational maturity includes firmware automation, fleet health telemetry, signal screening, power-delivery stress testing, precision liquid cooling, and proactive maintenance across GB200/GB300 deployments.

Summary based on 3 sources


Get a daily email with more Tech stories

More Stories