Lenovo 50M MLX HDR Optical QSFP56 CBL - 4Z57A72559

Lenovo 4Z57A72559 50M Mellanox HDR Optical QSFP56 Cable

Overview

The Lenovo 4Z57A72559 is a 50-meter active optical cable (AOC) with QSFP56 connectors supporting Mellanox HDR InfiniBand and 200GbE Ethernet — designed for high-bandwidth, long-reach interconnects inside datacenter fabric deployments where copper DAC cables fall short beyond 3–5 meters. At 200Gb throughput over 50 meters of fiber, this cable bridges top-of-rack switching to remote compute nodes, GPU clusters, or storage arrays without a transceiver and switch port penalty. Part number 4Z57A72559 is factory-terminated and Lenovo-qualified, meaning it integrates without firmware or compatibility workarounds in Lenovo ThinkSystem environments.

Compatibility

Designed for use with Lenovo ThinkSystem servers and adapters supporting HDR InfiniBand or 200GbE via QSFP56 interfaces. Pairs directly with the ThinkSystem Mellanox ConnectX-6 HDR/200GbE QSFP56 1-port PCIe 4 VPI Adapter (part 4C57A15326 / feature code B4RC) and its SharedIO DWC variants (CTO B4RG, 4XC7A86672 BKSK). Also compatible with the ThinkSystem Mellanox HDR/200GbE 2x PCIe Aux Kit (4C57A14179). Confirmed server platform support includes the SR650 V2. For SD665 V3 and SD650 V3 DWC sled environments, verify against the platform-specific SharedIO cable (BPZG / BRL2) before ordering — those sleds use dedicated internal cabling paths. This cable is not a drop-in replacement for the 100G QSFP28 AOC family (e.g., 4X97A94705) — connector and speed generation differ.

Installation Notes

Active optical cables require no separate transceivers but draw power from the host adapter port — confirm your ConnectX-6 adapter's per-port power budget supports the AOC at 50m length. Bend radius matters on fiber runs of this length: route with cable management arms rather than tight conduit bends to avoid signal attenuation. At 50 meters, plan the physical path carefully before ordering — shorter variants exist in the Lenovo AOC portfolio (1m through 30m) if the rack layout allows a shorter run.