NVIDIA Mellanox MCX566A-CDAB ConnectX-5 Ex EN Dual-Port 100GbE OCP 3.0 SFF Adapter, NEW: This is a ConnectX-5 Ex Ethernet-only adapter in the OCP 3.0 Small Form Factor (SFF) — not a standard PCIe card and not a discrete NIC with PCB-mounted bracket. The card has two QSFP28 ports operating at 100GbE per port, a PCIe Gen4 x16 host edge connector, and a thumbscrew (pull-tab) bracket for tool-less insertion into OCP 3.0 cages. NVIDIA P/N: 900-9X5AD-0066-DT0 (CDAB suffix). Host management is supported. This is a NEW (factory-sealed / unused) unit.
Engineering Context
OCP 3.0 SFF is a side-mounted server module standard adopted by major hyperscalers and OEMs (Dell, HPE, Supermicro, Lenovo) for management-network and high-bandwidth NIC slots. The CDAB suffix in the MCX566A product line indicates dual 100GbE QSFP28 ports with the C variant of host management. PCIe Gen4 x16 provides ~256 Gb/s of usable bandwidth, comfortably above the 200 Gb/s aggregate of two 100GbE ports. The card supports RoCEv2, NVMe-oF, ASAP² OVS offload, T10-DIF, and stateless TCP/UDP/IP offloads.
Deployment & Use Cases
OCP 3.0-equipped servers in cloud and hyperscaler fleets requiring dual 100GbE without consuming a standard PCIe slot. NVMe-oF storage targets and initiators on PCIe Gen4 platforms. Spectrum-2/Spectrum-3 100GbE leaf-and-spine fabrics. AI training nodes where the OCP 3.0 cage is reserved for the high-bandwidth NIC and standard PCIe slots are reserved for GPUs. Hyperconverged platforms and edge cloud nodes.
Technical Specifications
OEM: NVIDIA Mellanox
Part Number: MCX566A-CDAB
Family: ConnectX-5 Ex EN (Ethernet only)
Form Factor: OCP 3.0 Small Form Factor (SFF)
Ports: Dual QSFP28
Data Rate: 100GbE per port
Host Interface: PCIe Gen4 x16 (also runs on Gen3 x16)
Bracket: Thumbscrew with Pull Tab (tool-less)
Host Management: Supported (NC-SI / MCTP)
RDMA: RoCEv2
Offloads: NVMe-oF, T10-DIF, ASAP² OVS
Condition: New
Compatibility & Constraints
Requires a server with an OCP 3.0 SFF cage that exposes a PCIe Gen4 x16 (or Gen3 x16) host edge. Works with chassis from Dell PowerEdge, HPE ProLiant Gen10/11, Supermicro X11/X12, Lenovo ThinkSystem, and most ODM hyperscaler designs that follow OCP 3.0. Compatible with NVIDIA Spectrum/Spectrum-2/Spectrum-3 100GbE switches and any standards-based 100GbE fabric. Not a standard PCIe card — it will not seat in a regular PCIe slot. Not an InfiniBand card — EN variant has no IB support. Not compatible with OCP 2.0 mezzanine cages (different form factor and connector).
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS supplies new factory-sealed and refurbished Mellanox enterprise hardware. Visit https://www.tes-itsolutions.com/ for our full ConnectX-5/6/7 catalog. Handling time: 1–3 business days.