Networking & fabrics
InfiniBand and Spectrum-X Ethernet switches, adapters and DPUs: the fabric layer of a validated cluster.
NVIDIA Quantum-2 QM9700
The Quantum-2 QM9700 is a 1U, fixed-configuration NDR InfiniBand switch built around the Quantum-2 ASIC: 64 ports of 400 Gb/s NDR across 32 twin-port OSFP cages, 51.2 Tb/s of non-blocking aggregate throughput, and a 64-way radix that makes it the standard building block for H100 and H200 GPU fabrics. It ships as a managed switch (onboard x86 subnet manager, up to 2,000 nodes) or as an externally managed switch that hands subnet management to NVIDIA UFM. It supports SHARPv3 in-network reduction, adaptive routing and SHIELD self-healing link recovery. The same chassis serves as either leaf or spine in a two-tier fat-tree design, which is how most H100/H200 clusters still spec their fabric in 2026.
NVIDIA Quantum-X800
Quantum-X800 is NVIDIA's XDR-generation InfiniBand switch platform, built around the Quantum-3 ASIC and paired with Blackwell-class GPUs (GB200, B200, B300) over ConnectX-8/9 SuperNICs running at up to 1.6 Tb/s per GPU. The Q3400-RA is the 4U flagship: 144 ports of 800 Gb/s XDR across 72 twin-port OSFP cages, 115.2 Tb/s of non-blocking aggregate throughput, and sub-100 ns port-to-port latency. A smaller 2U Q3200-RA (72 ports, 57.6 Tb/s) covers lower-radix leaf roles or bridges legacy Quantum-2 fabrics into an XDR build. Both chassis run as leaf or spine in a two-tier fat tree, and NVIDIA's own reference design scales a single fat tree built from Q3400-RA switches to 10,368 NICs.
NVIDIA Spectrum-X SN5600
The SN5600 is a 64-port 800GbE Spectrum-4 switch and the leaf/spine building block of Spectrum-X, NVIDIA's Ethernet alternative to InfiniBand for AI training and inference fabrics. On its own it is a 51.2 Tb/s cut-through Ethernet switch. Paired with BlueField-3 SuperNICs on the host side, it becomes the full Spectrum-X stack: lossless RoCE, per-packet adaptive routing and telemetry-based congestion control tuned for GPU collective traffic. Buy it as a commodity switch or as one half of a matched fabric; the two behave very differently.
NVIDIA ConnectX-7
ConnectX-7 is the node-level network adapter of the H100/H200 generation: a 400 Gb/s PCIe Gen5 card that runs InfiniBand NDR or Ethernet from the same silicon (VPI). In a rail-optimized HGX design, one ConnectX-7 sits behind each GPU, PCIe-switch-attached so GPUDirect RDMA traffic never crosses the CPU root complex. The connector and protocol you order lock in the fabric you're building toward, InfiniBand for maximum determinism or Spectrum-X Ethernet for operational uniformity, so it is worth getting that decision right before ordering eight of these per node.