SXM vs PCIe

SXM and PCIe are the two form factors Nvidia ships data center GPUs in. The choice sets how a GPU gets power, cooling, and its path to other GPUs. An SXM module is a bare board with no fan or shroud that bolts into a socket on a vendor-specific baseboard, taking power and NVLink signals through that socket. A PCIe GPU is a standard add-in card with its own power connectors that drops into any qualified server slot.

Power and connectivity separate them. An H100 in SXM form runs up to 700 W and reaches the other seven GPUs on the baseboard through NVSwitch at full NVLink speed. The same H100 as a PCIe card is capped near 350 W and can bridge to one neighbor only. Everything past that pair crosses PCIe at a fraction of the rate. SXM baseboards, sold as HGX modules and built into DGX systems, also require a matched chassis and are not field-serviceable the way a card is.

PCIe is right for one or two GPUs in a standard server. SXM starts paying once you need eight GPUs holding full bandwidth to each other on a single job.

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Last verified August 29, 2026.