Dell MRT0D Mellanox CX4121C 2-Port 25Gbe SFP+ PCIe NIC

Dell Mellanox ConnectX-4 Lx 2-Port 25GbE SFP28 PCIe NIC

The Dell Part Number MRT0D (Alternate Part Numbers: 0MRT0D / Model: CX4121C) is an enterprise-class, high-performance 25 Gigabit Ethernet (25GbE) Dual-Port Network Interface Card (NIC). Powered by Mellanox (NVIDIA) ConnectX-4 Lx EN technology and designed for a standard PCI Express Gen3 x8 slot, this adapter is engineered for cloud-scale infrastructures, web-hosting clusters, virtualized enterprise data centers, and high-frequency storage setups.

It provides an efficient path for data centers to transition from 10GbE to 25GbE speeds while optimizing CPU utilization, reducing network latencies, and drastically lowering overall operational costs (TCO).

Key Features & Capabilities

• 25GbE Port Density: Features two SFP28 ports capable of delivering 25 Gbps line-rate bandwidth per port concurrently, solving bottleneck constraints in heavy multi-tenant or virtualized environments.

• RoCE (RDMA over Converged Ethernet): Supports RoCE v1 and RoCE v2, allowing direct memory transfers between servers without processor intervention. This enables ultra-low latency and accelerates NVMe-oF (NVMe over Fabrics) storage workloads.

• Hardware Virtualization & Offloads: Built-in SR-IOV (Single Root I/O Virtualization) handles up to 128 virtual functions per port. It features hardware-based overlay network offloads for VXLAN, NVGRE, and Geneve, reducing host CPU strain.

• Erasure Coding Offload: Offloads storage Reed-Solomon erasure coding calculations directly to the network controller ASIC, accelerating distributed object storage systems.

• Flexible Speed Adaptation: The underlying SFP28 cages are backward-compatible with standard 10GbE SFP+ optical transceivers and Direct Attach Copper (DAC) cables, offering a reliable stepping stone for network staging.

Technical Specifications