NVIDIA Mellanox ConnectX-4 MCX456A-FCAT
Dual-Port VPI Adapter, 56Gb/s InfiniBand FDR / 56GbE, PCIe 3.0 x16, QSFP28
Host Interface
PCIe 3.0 x16
Port Count
2-port
Port Speed & Connector Type
56Gb/s IB(FDR) / 56GbE, QSFP28
Adapter Type
VPI dual-protocol (InfiniBand & Ethernet)
RDMA / Network Protocol
Native InfiniBand RDMA; RoCE v2 over Ethernet
Product Description
The NVIDIA Mellanox ConnectX-4 MCX456A-FCAT is a dual-port Virtual Protocol Interconnect (VPI) adapter delivering 56Gb/s InfiniBand FDR or 56GbE Ethernet connectivity from two QSFP28 ports on a single card. Its PCIe 3.0 x16 host interface provides full bandwidth headroom for both ports to operate at line rate simultaneously, distinguishing it from the PCIe 3.0 x8 dual-port MCX454A-FCAT, which shares less host bandwidth across the same two ports. Built around the Mellanox MT27704A0-FDCF-FV controller, it supports both native InfiniBand RDMA and RoCE v2 for low-latency, CPU-offloaded data movement, making it well suited to HPC clusters, storage fabrics, and virtualized data centers with demanding dual-port throughput requirements. As part of the ConnectX-4 generation (circa 2015-2018), it is a widely deployed, field-proven interconnect for enterprise and HPC infrastructure needing maximum per-port bandwidth alongside flexible fabric choice.