NVIDIA Mellanox® MCX4431N-GCAN — ConnectX-4 Lx 50GbE Single-Port SFP28 Adapter
Technical Identity
The NVIDIA Mellanox® MCX4431N-GCAN is a single-port 50GbE Ethernet network adapter built on the ConnectX-4 Lx ASIC, with one SFP28 cage on a low-profile PCIe 3.0 x8 card. Lx is an Ethernet-only ASIC line — it has no InfiniBand mode and is not VPI. Supplied Refurbished Grade A, bench-tested by T.E.S IT-SOLUTIONS for link, signal integrity, and EEPROM identity before shipment.
Specifications
Brand: NVIDIA Mellanox
Model / MPN: MCX4431N-GCAN
Product family: ConnectX Network Adapter
ASIC / Generation: ConnectX-4 Lx
Protocol: Ethernet only (no InfiniBand, no VPI)
Ports: 1 × SFP28
Rated speed: 50GbE (port also negotiates 25GbE and 10GbE)
Host interface: PCIe 3.0 x8
Form factor: Low-profile PCIe card (OCP-style mezz variants use a different MPN)
Hardware offloads: RoCE v1/v2, SR-IOV, ASAP² (hardware Open vSwitch), VXLAN/NVGRE/Geneve/GTP encap/decap, T10-DIF, stateless TCP/UDP offloads
Condition: Refurbished Grade A — bench-tested by T.E.S IT-SOLUTIONS
What This Is NOT
NOT an InfiniBand or VPI adapter. ConnectX-4 Lx is Ethernet-only and cannot be switched to InfiniBand via mlxconfig. If you need VPI or native IB, look at ConnectX-5 VPI, ConnectX-6 VPI, or ConnectX-7.
NOT a 100GbE card. Maximum line rate is 50GbE; the SFP28 port physically cannot present 100GbE.
NOT a QSFP-family adapter. The cage is SFP28 and will not accept any QSFP+, QSFP28, QSFP56 or OSFP transceiver / DAC.
NOT a dual-port card. Single physical port, single PCIe device.
NOT an OCP / Multi-Host variant. Standard low-profile PCIe form factor; the Multi-Host / socket-direct SKUs carry different MPNs.
NOT bundled with transceivers, DACs, full-height bracket, or cables — sold standalone.
Compatibility
Host: Server with an available PCIe 3.0 x8 (or wider) slot. Backward compatible into PCIe 2.0 slots at reduced bandwidth.
Operating systems / drivers: NVIDIA MLNX_OFED or DOCA-Host (Linux), in-box mlx5_core (upstream Linux), WinOF-2 (Windows Server 2016/2019/2022), nmlx5 (VMware ESXi).
Switches (pairs with, not part of the product): NVIDIA Spectrum SN2010 / SN2410 / SN2700 25/50/100 GbE, Spectrum-2 SN3000-series, or any third-party Ethernet switch with SFP28 ports or QSFP28-to-SFP28 breakouts.
Cabling (pairs with, sold separately): SFP28 passive DAC, active DAC, AOC, or short-reach SFP28 optical transceivers; QSFP28-to-4×SFP28 splitter cables on the switch side.
Storage fabric: NVMe-oF over RoCE v2 initiator/target.
Frequently Asked Questions (FAQ)
Q. What is the NVIDIA Mellanox MCX4431N-GCAN?
The MCX4431N-GCAN is a single-port 50GbE Ethernet network adapter built on the ConnectX-4 Lx ASIC with one SFP28 cage, in a low-profile PCIe 3.0 x8 card form factor. Ethernet only (Lx ASIC, no native InfiniBand, no VPI).
Q. What connector and speeds does the MCX4431N-GCAN support?
One SFP28 cage. Rated at 50GbE; the SFP28 port is also backward compatible with 25GbE and 10GbE link rates when paired with matching cables and transceivers. It will not accept any QSFP, QSFP28, QSFP56 or OSFP module.
Q. What switches and cables work with the MCX4431N-GCAN?
Typical head-end switches: NVIDIA Spectrum SN2010 / SN2410 / SN2700 (25/50/100 GbE) or any Ethernet switch presenting SFP28 ports (directly or via QSFP28-to-SFP28 breakout). Cabling: passive/active SFP28 DAC, SFP28 AOC, or SFP28 short-reach optical transceivers. Confirm the upstream switch port is configured for 50GbE or 25GbE before deployment.
Q. Does the MCX4431N-GCAN support RDMA and InfiniBand?
The MCX4431N-GCAN supports RDMA via RoCE v1 and v2 (RDMA over Converged Ethernet) plus full hardware offloads (SR-IOV, ASAP² OVS, VXLAN/NVGRE/Geneve encap/decap, T10-DIF). It does NOT support native InfiniBand — the ConnectX-4 Lx ASIC is Ethernet-only. For VPI dual-protocol or native IB, use ConnectX-5 VPI, ConnectX-6 VPI, or ConnectX-7.
Q. Which drivers does the MCX4431N-GCAN require?
NVIDIA MLNX_OFED or DOCA-Host for Linux, in-box mlx5_core in modern upstream kernels, WinOF-2 for Windows Server, and nmlx5 for VMware ESXi. Match the driver bundle to the firmware revision flashed on the card.
Q. What workloads does the MCX4431N-GCAN accelerate?
25/50 GbE NVMe-oF storage initiators and targets, virtualized data-center hosts with SR-IOV and ASAP² hardware OVS, software-defined networking (SDN / NFV) with VXLAN/Geneve offloads, and RoCE-based RDMA workloads where a single 50GbE uplink is sufficient.
Q. What condition is supplied by T.E.S IT-SOLUTIONS?
Refurbished Grade A. Each unit is bench-tested by T.E.S IT-SOLUTIONS: PCIe link train, port link-up at 50GbE, EEPROM / vendor data check, and full cosmetic inspection. Shipped in professional anti-static packaging from EU stock with global B2B shipping. Pre-sale compatibility advice for switch, cable, and transceiver pairing is included.
Why buy from T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS is a Europe-based NVIDIA Mellanox specialist serving HPC, AI, and enterprise data-center procurement teams since 2007. Every adapter is identified by MPN, NVIDIA P/N, and ASIC generation before it ships, bench-tested in a real PCIe host, and shipped in professional anti-static packaging from EU stock. Multi-currency B2B invoicing, worldwide express options, free pre-sale switch/cable/transceiver compatibility advice, and direct contact with our engineering team — not a call-center.