xAI picked Ethernet over InfiniBand for its H100 Colossus training cluster

Work already underway to expand system to 200,000 Nvidia Hopper chips

Unlike most AI training clusters, xAI's Colossus with its 100,000 Nvidia Hopper GPUs doesn't use InfiniBand. Instead, the massive system, which Nvidia bills as the "world's largest AI supercomputer," was built using the GPU giant's Spectrum-X Ethernet fabric....