NVIDIA Mellanox MCX416A-BCAT ConnectX-4 EN, 40/56GbE Dual-Port QSFP28 PCIe Gen3 x16 Adapter: This is a standard PCIe slot network interface card based on the ConnectX-4 EN Ethernet controller. It provides two QSFP28 ports configurable for 40GbE or 56GbE Ethernet, with a PCIe Gen3 x16 host interface and a tall (full-height) bracket. The x16 host interface is the key differentiator from the MCX414A-BCAT (x8), enabling full line-rate concurrent throughput on both ports. This is a tall-bracket card — it is NOT half-height. This is a refurbished unit, tested by T.E.S IT-SOLUTIONS.
Engineering Context
PCIe Gen3 x16 delivers 128 Gb/s of effective host bandwidth — enough to sustain 56GbE on both ports concurrently. On the x8 sibling (MCX414A-BCAT) aggregate throughput is bus-bound when both ports run at 56GbE; the x16 BCAT removes that ceiling. The ConnectX-4 EN controller offers RoCE v1/v2, hardware overlay tunneling (VXLAN, NVGRE, GENEVE), Open vSwitch acceleration, SR-IOV (up to 128 VFs), T10-DIF, and stateless TCP/UDP/IP offloads. 56GbE is Mellanox FDR-based Ethernet (14 Gb/s x 4 lanes).
Deployment & Use Cases
Bandwidth-bound workloads where both ports must run concurrently at full rate: hyper-converged storage spines, GPU compute servers feeding NVMe-oF arrays, in-memory database replication, and high-frequency analytics. RoCE-based RDMA fabrics for HPC and machine learning training clusters. Aggregation servers in private and hybrid clouds.
Technical Specifications
OEM: NVIDIA Mellanox
Part Number: MCX416A-BCAT
Controller: ConnectX-4 EN
Form Factor: Standard PCIe Card
Ports: Dual-Port (2x QSFP28)
Data Rate: 40GbE / 56GbE per port
Host Interface: PCIe Gen3 x16 (8 GT/s)
Bracket: Tall (Full-Height)
Offloads: RoCE v1/v2, SR-IOV, VXLAN, NVGRE, GENEVE, OVS
Compliance: RoHS R6
Condition: Refurbished — Tested by T.E.S IT-SOLUTIONS
Compatibility & Hard Constraints
Requires a free PCIe Gen3 x16 (or wider) slot to achieve full bandwidth. Will physically seat in a x16 connector wired electrically as x8, but will then operate at x8 lane width with reduced aggregate throughput. 56GbE rate is supported only with NVIDIA/Mellanox 56GbE-capable switches and matching FDR cables. Compatible with Mellanox-certified QSFP+/QSFP28 DACs, AOCs, and transceivers. Ethernet only (BCAT is not VPI/InfiniBand). Drivers: NVIDIA MLNX_OFED, MLNX_EN, or in-box Linux/Windows.
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS tests every refurbished ConnectX-4 EN x16 adapter for dual-port link-up at 40GbE and 56GbE, PCIe x16 lane training, and port LED indication before shipment. Orders ship within 1–3 business days with global delivery and warranty coverage.