NVSwitch

NVSwitch is the crossbar that connects 8 (or in NVL72, 72) GPUs into a single all-to-all NVLink fabric. Each GPU talks to every other GPU at full NVLink speed simultaneously, which is what makes 8× H100 SXM systems behave like a single huge accelerator for tensor parallelism.

In NVL72 (Blackwell), 72 GPUs share one NVLink domain — the largest coherent GPU group ever shipped. This is the hardware that makes very-large-model inference (Llama 4 Behemoth, DeepSeek-V3 at full scale) practical.

Not relevant for consumer local AI; this is data-center-only fabric.