NVIDIA Mellanox MCX556A-EDAT ConnectX-5 Ex VPI Dual-Port QSFP28 Adapter Card, EDR InfiniBand 100Gb/s and 100GbE, PCIe Gen4: This is a dual-port ConnectX-5 Ex VPI (Virtual Protocol Interconnect) Host Channel Adapter / Network Interface Card with two QSFP28 ports, supporting either EDR InfiniBand 100Gb/s or 100GbE per port over a PCIe Gen4 x16 host interface. The card is a server add-in adapter; it is NOT a switch, transceiver, or cable. NVIDIA P/N: 900-9X5AD-0056-STB. Refurbished, in TES IT-SOLUTIONS stock.
Engineering Context: ConnectX-5 Ex extends the ConnectX-5 family with PCIe Gen4 x16 support, delivering host bus headroom for full dual-port 100Gb/s line rate without bus saturation. The silicon supports VPI mode (per-port InfiniBand or Ethernet selection), advanced RDMA (InfiniBand native and RoCE v1/v2 over Ethernet), and a hardened set of hardware offloads including SR-IOV, GPUDirect RDMA, NVMe-over-Fabrics target/initiator offloads, T10-DIF/PI signature handling, ASAP² eSwitch acceleration, and stateless TCP/UDP offloads. NRZ encoding at 4×25.78125 Gb/s drives 100Gb/s aggregate per port.
Deployment & Use Cases: Targeted at high-performance compute (HPC) clusters, GPU-accelerated AI/ML training nodes, NVMe-oF storage initiators and targets, low-latency financial trading, hyperconverged infrastructure (Storage Spaces Direct, vSAN, Ceph), and software-defined networking deployments using ASAP² for OVS offload. Pairs with EDR InfiniBand fabrics built on Mellanox SB7700/SB7800/SB7890 switches or 100GbE Spectrum-based deployments.
Technical Specifications:
MPN: MCX556A-EDAT
NVIDIA P/N: 900-9X5AD-0056-STB
Silicon: ConnectX-5 Ex VPI
Ports: 2× QSFP28
Per-Port Rate: 100Gb/s
Protocols: EDR InfiniBand 100Gb/s and 100GbE (per-port selectable)
Host Interface: PCIe Gen4 x16 (backward compatible with Gen3 x16)
RDMA: InfiniBand native, RoCE v1/v2
Offloads: SR-IOV, GPUDirect RDMA, NVMe-oF, T10-DIF/PI, ASAP² eSwitch
Encoding: NRZ (4× 25.78125 Gb/s per port)
Form Factor: Standard PCIe (low-profile/full-height bracket)
Condition: Refurbished
Compatibility & Constraints: Requires a PCIe Gen4 x16 slot for full headroom (will negotiate down on Gen3 with reduced ceiling for full dual-port line rate). Each QSFP28 port operates independently as IB or Ethernet but cannot run both protocols simultaneously on the same port. The MCX556A-EDAT is the dual-port ConnectX-5 Ex variant; it is NOT the single-port MCX555A-ECAT, and it is NOT the HDR (200Gb/s) ConnectX-6 family. QSFP28 cabling is required and sold separately.
Why TES: T.E.S IT-SOLUTIONS ships from EU stock with 1–3 day handling. Each refurbished card is inspected and functionally tested. Contact our team for firmware guidance, PCIe slot verification, and bulk pricing on cluster builds.
Frequently Asked Questions
What is the MCX556A-EDAT NOT compatible with?
it is NOT a switch, transceiver, or cable. Confirm fitment against your platform before ordering MCX556A-EDAT.
What condition is the MCX556A-EDAT supplied in, and who sells it?
The MCX556A-EDAT is supplied in Refurbished condition by T.E.S IT-SOLUTIONS from EU stock, with 1-3 business day handling and worldwide B2B shipping. See https://www.tes-itsolutions.com/product-page/mellanox-mcx556a-edat-connectx-5-ex-vpi-adapter-card-edr-ib-100gbe.
Are there deployment constraints on the MCX556A-EDAT?
Each QSFP28 port operates independently as IB or Ethernet but cannot run both protocols simultaneously on the same port. This applies to MCX556A-EDAT specifically.