NVIDIA Mellanox® MCB194A-FCAT — Connect-IB™ Dual-Port FDR 56Gb/s InfiniBand Host Channel Adapter, PCIe 3.0 x16

Technical Identity
The NVIDIA Mellanox MCB194A-FCAT is a Connect-IB™ generation, dual-port FDR 56 Gb/s InfiniBand Host Channel Adapter (HCA) on a PCIe 3.0 x16 host interface, with two QSFP ports. Built on Mellanox's Connect-IB silicon — the HCA generation that sits between ConnectX-3 and ConnectX-4 and the first card to introduce Dynamically Connected Transport (DCT) — it is designed for HPC clusters, low-latency financial trading fabrics, and high-throughput storage back-ends. This is an InfiniBand-only adapter; it does not support Ethernet and is not a VPI card.

Specifications

OEM: NVIDIA Mellanox
Manufacturer Part Number (MPN): MCB194A-FCAT
Product Family / ASIC: Connect-IB™ (pre-ConnectX-4 generation)
Ports: 2× QSFP (dual-port)
Port Speed: 56 Gb/s FDR InfiniBand per port (auto-negotiates down to FDR10, QDR 40 Gb/s, DDR 20 Gb/s)
Aggregate Bandwidth: Up to 112 Gb/s bidirectional
Host Interface: PCI Express Gen 3.0 x16 (8 GT/s per lane)
Protocol Support: InfiniBand only — Ethernet / VPI NOT supported
Message Rate: Up to 137 million messages per second
Latency: Sub-microsecond MPI ping-pong (port-to-port)
RDMA & Offloads: RDMA, GPUDirect™ RDMA, SR-IOV, CORE-Direct®, hardware tag matching, Dynamically Connected Transport (DCT)
Form Factor: Standard / Low-Profile (MD2) PCIe HHHL
Driver Stack: MLNX_OFED 2.x – 4.x, in-distro OFED (RHEL/CentOS, SLES, Ubuntu), Windows OFED, ESXi
Condition: New, factory-sealed


What This Is NOT

NOT a ConnectX-3, ConnectX-4, ConnectX-5, ConnectX-6, or ConnectX-7 card. Connect-IB is its own ASIC family with separate firmware (PSID) and driver feature gates.
NOT an EDR (100 Gb/s), HDR (200 Gb/s), or NDR (400 Gb/s) HCA. Maximum link rate is FDR 56 Gb/s per port.
NOT VPI / NOT Ethernet-capable. The Connect-IB ASIC does not implement Ethernet — for dual-protocol use a ConnectX-3 VPI or ConnectX-4/5/6 VPI card.
NOT a SmartNIC or DPU. No on-card ARM cores or programmable data path — see BlueField-2 / BlueField-3 for DPU functionality.
NOT a switch. This is a host adapter and requires an FDR-capable InfiniBand switch upstream.
NOT bundled with cables, transceivers, or brackets unless explicitly stated.


Compatibility

InfiniBand Switches (pairs with): Mellanox SX6018, SX6025, SX6036, SX6512, SX6710, SX6790 FDR InfiniBand switches; also backward compatible with QDR switches (IS5030, IS5035, SX6036 in QDR mode).
Cables & Transceivers (pairs with): Mellanox MC2207130 / MC2207128 / MC220731V series QSFP+ FDR copper (DAC), MC2207310 / MC220731V series active optical cables (AOC), and Mellanox LinkX FDR optical transceivers + OM3/OM4 multi-mode fibre.
Servers: Any server with a free PCIe Gen 3.0 x16 slot — Dell PowerEdge R720/R730, HPE ProLiant DL380 Gen8/Gen9, Supermicro X9/X10, Lenovo ThinkSystem (validated under MLNX_OFED). Will operate in a PCIe 3.0 x8 slot at reduced aggregate bandwidth.
Drivers: MLNX_OFED 2.x through 4.x (Connect-IB is end-of-active-development in MLNX_OFED 5.x+; for newer driver stacks migrate to ConnectX-4 or later).
GPUDirect RDMA: Validated with NVIDIA Kepler and Pascal Tesla GPUs (K20, K40, K80, P100) on CUDA 6.5–9.x.
Operating Systems: RHEL/CentOS 6.x–7.x, SLES 11/12, Ubuntu 14.04/16.04/18.04, Windows Server 2012 R2 / 2016, VMware ESXi 5.x/6.x.


FAQ
Q: What is the NVIDIA Mellanox MCB194A-FCAT?
A: The MCB194A-FCAT is a Connect-IB™ generation, dual-port FDR 56 Gb/s InfiniBand Host Channel Adapter on a PCIe 3.0 x16 host interface, with 2× QSFP ports. It is InfiniBand-only and does not support Ethernet.

Q: Is the MCB194A-FCAT a ConnectX adapter?
A: No. Connect-IB is its own ASIC family — released between ConnectX-3 and ConnectX-4 — with separate firmware images and driver paths. It is not interchangeable with ConnectX-3 or ConnectX-4 cards.

Q: Can the MCB194A-FCAT run Ethernet?
A: No. The Connect-IB silicon is InfiniBand-only. For dual-protocol (VPI) cards that switch between InfiniBand and Ethernet, use ConnectX-3 VPI, ConnectX-4 VPI, ConnectX-5 VPI, or ConnectX-6 VPI.

Q: Which switches and cables does it work with?
A: Any FDR InfiniBand switch — Mellanox SX6xxx series — using standard QSFP+ FDR DAC or AOC cables (Mellanox MC22071xx / MC22073xx families) and LinkX FDR optical transceivers. It will also negotiate down to QDR (40 Gb/s) on legacy QDR fabrics.

Q: What PCIe slot does it require?
A: PCI Express Gen 3.0 x16 for full dual-port FDR bandwidth. It will fit and operate in a PCIe 3.0 x8 slot, but aggregate throughput is approximately halved.

Q: Is this a new or refurbished unit?
A: New, factory-sealed in original NVIDIA Mellanox packaging where included.

Why T.E.S IT-SOLUTIONS
Every MCB194A-FCAT shipped by T.E.S IT-SOLUTIONS is bench-tested under MLNX_OFED — dual-port link-up validation, firmware / PSID verification, PCIe link-width confirmation, and full cosmetic inspection. Anti-static professional packaging, EU stock with global B2B express shipping, multi-currency invoicing, and direct technical pre-sales consultation for HPC, GPU-cluster, and InfiniBand-storage deployments — speak to our engineering team, not a call-center.