NVIDIA Mellanox MCX314A-BCBT ConnectX-3 EN 40/56GbE Dual-Port QSFP NIC: This is a dual-port Ethernet Network Interface Card (NIC) built on the Mellanox ConnectX-3 ASIC, supporting 40GbE and 56GbE rates over QSFP+ ports in a PCI Express 3.0 x8 host interface. This is an Ethernet-only adapter (EN) — it does NOT support InfiniBand operation; for dual-protocol VPI capability, use the ConnectX-3 VPI series. This is a brand-new, factory-sealed unit.
Engineering Context
The MCX314A-BCBT delivers up to 56Gb/s per port using Mellanox's proprietary 56GbE mode over QSFP+ on capable Mellanox switches; with non-Mellanox switches, ports operate at the IEEE 802.3ba 40GbE rate. The ConnectX-3 ASIC supports stateless TCP/UDP/IP offloads, RDMA over Converged Ethernet (RoCE), SR-IOV with up to 127 virtual functions per port, and hardware-based VXLAN/NVGRE overlay encapsulation. The PCIe 3.0 x8 host bus provides up to 64 Gb/s of raw bandwidth, sufficient for dual-port 40GbE line-rate operation. Tall bracket configuration suits standard 2U+ servers.
Deployment & Use Cases
High-throughput east-west data center fabrics, Hadoop and Spark cluster nodes, NVMe-oF over RoCE storage targets, Ceph and GlusterFS distributed storage backends, virtualization hosts running VMware ESXi or KVM with SR-IOV passthrough, and 40GbE network function virtualization (NFV) workloads. Suitable for spine-leaf fabric uplinks on commodity x86 servers.
Technical Specifications
OEM: NVIDIA Mellanox
Part Number (MPN): MCX314A-BCBT
ASIC: ConnectX-3
Adapter Family: ConnectX-3 EN (Ethernet only)
Ports: 2 × QSFP+
Data Rates: 40GbE (IEEE) and 56GbE (Mellanox proprietary, switch-dependent)
Host Interface: PCIe 3.0 x8
Form Factor: Standard PCIe with tall bracket
Offloads: RoCE, TCP/UDP/IP stateless, SR-IOV (up to 127 VFs/port), VXLAN, NVGRE
RoHS: R6 compliant
Condition: Brand New — Factory Sealed
Compatibility & Constraints
Requires a free PCIe 3.0 x8 (or wider) slot. Compatible with Mellanox SX/MSX switches and IEEE 40GbE switches from Cisco, Arista, Juniper, and HPE. 56GbE rate requires Mellanox switches and Mellanox copper or active fiber cables. Not compatible with InfiniBand fabrics. Not a VPI adapter — does not auto-negotiate to InfiniBand. Supports Linux (RHEL, SLES, Ubuntu), Windows Server, VMware ESXi, and FreeBSD with MLNX_OFED or inbox drivers. Tall bracket only — no low-profile bracket included.
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS supplies NEW, factory-sealed Mellanox networking hardware with verified part-number authenticity. Visit tes-itsolutions.com for the full ConnectX catalog, expert pre-sales consultation on fabric design, global shipping with 1–3 business day handling, and warranty support.