NVIDIA Mellanox MCX345A-BCQN ConnectX-3 Pro EN OCP Single-Port 40GbE QSFP+ Network Interface Card: This is an OCP 2.0 mezzanine network adapter built on the ConnectX-3 Pro EN silicon. It is a single-port 40GbE Ethernet NIC with a QSFP+ cage, intended for OCP-compliant server chassis. This is a NIC, not a switch and not a host bus adapter. This is a refurbished unit.
Engineering Context
The MCX345A-BCQN uses the ConnectX-3 Pro EN ASIC and exposes a PCIe 3.0 x8 host interface. The OCP 2.0 mezzanine form factor places the adapter on a custom Open Compute Project carrier instead of a standard low-profile PCIe slot. NC-SI sideband enables BMC management traffic over the same physical port. The adapter supports stateless TCP/UDP/IP offloads, RDMA over Converged Ethernet (RoCE), and SR-IOV virtualization. It is driven by the mlx4_core and mlx4_en drivers in mainline Linux.
Deployment & Use Cases
OCP-compliant Open Rack and white-box server chassis requiring single-port 40GbE uplinks. Edge compute nodes, virtualization hosts, and storage front-ends in environments standardized on the OCP 2.0 mezzanine pinout. Workloads benefiting from RoCEv2 such as Microsoft Storage Spaces Direct, Hadoop shuffle traffic, and SR-IOV-based VM networking.
Technical Specifications
- OEM: NVIDIA Mellanox
- Part Number: MCX345A-BCQN
- Silicon: ConnectX-3 Pro EN
- Form Factor: OCP 2.0 Mezzanine
- Port Configuration: Single-Port QSFP+
- Data Rate: 40GbE Ethernet
- Host Bus: PCIe 3.0 x8
- Driver: mlx4_core / mlx4_en
- Management: NC-SI sideband for BMC
- Offloads: RoCE, SR-IOV, stateless TCP/UDP/IP
- Compliance: RoHS
- Condition: Refurbished — Tested by T.E.S IT-SOLUTIONS
Compatibility & Constraints
Requires a server chassis with an OCP 2.0 mezzanine slot; this card will NOT install in a standard PCIe expansion slot. Driven by mlx4 (legacy) drivers, not the mlx5 stack used by ConnectX-4 and newer adapters. This is a 40GbE Ethernet (EN) part — it does not run InfiniBand and is not a VPI dual-protocol card. Supports passive copper QSFP+ DAC, AOC, and SR4/LR4 transceivers; verify cable length and switch FEC support before deployment.
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS link-tests every NIC, verifies PCIe enumeration, and inspects the OCP edge connector before shipment. Visit tes-itsolutions.com for global shipping with 1–3 day handling.