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NVIDIA Q3450-LD (Quantum-X Photonics)

144 × 800G in 4U. That is 115.2 Tb/s of switching through 144 OSFP cages.

Breakout

A port faster than the endpoint it serves can be broken out when the speeds divide cleanly. That raises the usable port count. Two-tier capacity goes as the square of the port count, so it moves the tier boundary a long way.

Endpoint speedBreakoutUsable ports
800G none 144
400G 2:1 288
200G 4:1 576
100G 8:1 1,152

Roles and optics

Coding matters more than it looks. A switch may refuse a transceiver that is not coded for it, and that is one of six axes that have to agree before a link comes up. The others are form factor, reach, fibre type, fibre connector and ferrule polish. See optics compatibility.

Notes

Co-packaged optics, and the first such switch in this catalog. There are no transceiver cages: 144 XDR ports at 800 Gb/s attach fibre directly by MPO, which is why a BOM using it orders no optics for the switch end. That is the point of the design — electrical loss drops from roughly 22 dB to 4 dB because the signal never crosses a pluggable interface, and the switch draws about half what an equivalent pluggable design would. 4RU, liquid-cooled, four Quantum-X chips. UNCONFIRMED: power, and the faceplate fibre connector. MPO-12 and MPO-16 trunks are not interchangeable, so confirm against the NVIDIA cabling guide before ordering.

Source: NVIDIA Q32xx and Q34xx XDR 800Gb/s InfiniBand Switch Systems user manual (docs.nvidia.com/networking/display/XDRSwitchesHWUM) for ports, form factor, chip count, SKU and liquid cooling, verified 2026-09. POWER IS NOT FROM NVIDIA: the ~3.95 kW figure comes from third-party coverage and is unconfirmed. Needs verification

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