NVIDIA Mellanox ConnectX-4 Lx EN MCX4121A-ACST
Dual-Port 25GbE SFP28 Adapter with Secure Firmware, PCIe 3.0 x8
Host Interface
PCIe 3.0 x8
Port Count
2-port
Port Speed & Connector Type
25GbE, SFP28
Form Factor
Standard PCIe adapter, tall bracket
RDMA / Network Protocol
RoCE v2 (RDMA over Converged Ethernet)
Product Description
The NVIDIA Mellanox ConnectX-4 Lx EN MCX4121A-ACST is a dual-port 25 Gigabit Ethernet adapter built around Secure Firmware protection, which guards the adapter's onboard firmware image against unauthorized modification — an important control for security-conscious enterprise and service-provider environments. The card carries the same core ConnectX-4 Lx data path as the rest of the MCX4121A family: a PCIe 3.0 x8 host interface, two SFP28 ports at up to 25Gb/s each, and hardware-offloaded RDMA over Converged Ethernet (RoCE v2) for low-latency, low-CPU networking. SR-IOV, hardware QoS, stateless CPU offloads, jumbo frame support and RoCE-based storage acceleration round out the feature set for virtualized and storage-heavy workloads. Built on the single-chip MT27712A0-FDCF-AE controller, the ACST variant is positioned for deployments where firmware integrity assurance is a procurement requirement, while NC-SI, LLDP and QCN support keep the adapter manageable and congestion-aware within managed Ethernet fabrics.