storagereview.com › news AMD MI455X and Helios: 432GB HBM4, 72-GPU Racks, and a Real Answer to Vera Rubin … A customer could conceivably build a two-socket tray to match NVIDIA’s 1:2 CPU-to-GPU ratio, or retune the xGMI links to raise effective CPU-to-GPU bandwidth. … Jul 23, 2026