NVIDIA Mellanox MCX631102AN-ADAT ConnectX-6 Lx EN 25GbE Dual-Port SFP28 PCIe 4.0 x8 Adapter: This is a standard PCIe HHHL add-in network interface card based on the ConnectX-6 Lx EN ASIC, providing two SFP28 ports for 25GbE Ethernet connectivity. The card uses a PCIe 4.0 x8 host interface and ships with a tall (full-height) bracket. This is the cost-optimized Lx variant of the ConnectX-6 family — it is not a ConnectX-6 Dx and does not include hardware crypto offload (No Crypto). This is a refurbished unit.
Engineering Context
The ConnectX-6 Lx EN delivers up to 25 Gb/s per port for a dual-port aggregate of 50 Gb/s, with hardware acceleration for RoCEv2, SR-IOV, NVMe-oF (target and initiator), and ASAP² accelerated switching. The PCIe 4.0 x8 host interface provides headroom even at full line rate and is backward compatible with PCIe 3.0 x8. The Lx variant is designed for cost-efficient 25GbE deployments where IPsec/TLS hardware offload and Mellanox SmartNIC features are not required. Power envelope is low for high-density rack deployments.
Deployment & Use Cases
Enterprise virtualization clusters (VMware vSphere, KVM, Hyper-V) requiring 25GbE with SR-IOV. Cloud-native and Kubernetes nodes with high pod density. Storage targets and initiators using RoCEv2 and NVMe-oF over Ethernet. Leaf-tier servers in spine-leaf data center fabrics. Edge and ROBO server deployments where PCIe 4.0 x8 and dual-port 25GbE are sufficient.
Technical Specifications
OEM: NVIDIA Mellanox
Part Number: MCX631102AN-ADAT
Controller: ConnectX-6 Lx EN
Ports: Dual-Port SFP28
Port Speed: 25GbE per port (50GbE aggregate)
Host Interface: PCIe 4.0 x8 (backward compatible with PCIe 3.0 x8)
Form Factor: PCIe HHHL add-in card
Bracket: Tall (full-height) bracket
Protocol: Ethernet only (EN)
RDMA: RoCEv2
Storage Offload: NVMe-oF target & initiator
Virtualization: SR-IOV, ASAP²
Crypto: No Crypto (not a Dx variant)
Condition: Refurbished — Tested by T.E.S IT-SOLUTIONS
Compatibility & Hard Constraints
Requires a server with an available PCIe 4.0 x8 slot (PCIe 3.0 x8 supported at reduced bandwidth). Requires SFP28 transceivers or SFP28 DAC/AOC cables; not compatible with QSFP28 cages. EN suffix indicates Ethernet-only operation; the card cannot be reconfigured for native InfiniBand. This is the Lx (cost-optimized) variant — it does not include hardware IPsec or TLS offload; for those features, the ConnectX-6 Dx (MCX623* series) is required. Tall bracket only as supplied; low-profile bracket is not included. Requires NVIDIA OFED or in-box mlx5 drivers (Linux kernel ≥4.14, Windows Server 2016 or later).
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS verifies link training on both SFP28 ports, PCIe link width and speed, and firmware level on every refurbished MCX631102AN-ADAT before shipment. We provide expert consultation on NVIDIA Mellanox networking, global shipping, and 1–3 day handling. Visit tes-itsolutions.com for our full catalog.