- Dual-Port 25GbE Connectivity: LinksTek CX4121A is a dual-port 25GbE SFP28 Ethernet network adapter designed for high-performance servers, data centers, virtualization, cloud computing, web infrastructure, data analytics, databases, storage, and telecommunications platforms. Powered by the Mellanox ConnectX-4 Lx EN MT27711A0 Ethernet controller, it supports two simultaneous 25GbE connections with RDMA and advanced network offloading capabilities.
- Hardware Specifications: Controller: Mellanox ConnectX-4 Lx EN MT27711A0; Host Interface: PCI Express 3.0 x8; Network Ports: 2x SFP28; Maximum Data Rate: 25Gbps per port, 50Gbps aggregate. The PCIe interface provides 8 GT/s per lane and 64Gbps of raw aggregate signaling bandwidth. Supports PCIe x8 and x16 physical slots and is backward compatible with PCIe Gen 2.0.
- RDMA and Virtualization: Supports RDMA over Converged Ethernet (RoCE), including RoCE v2, Single Root I/O Virtualization (SR-IOV), and advanced I/O virtualization. Supports up to 512 virtual functions and 16 physical functions, according to the manufacturer's specifications. Additional capabilities include network overlay offloading for VXLAN and NVGRE, Multi-Host technology, and PeerDirect data movement.
- Storage and Remote Boot: Supports storage protocols and technologies including SRP, iSER, NFS, RDMA, SMB Direct, and NVMe over Fabrics (NVMe-oF). Remote boot capabilities include PXE, iSCSI, UEFI, and Ethernet boot, subject to driver and system configuration.
- Ethernet Standards and Features: Supports IEEE 802.3by 25GbE, IEEE 802.3ae 10GbE, IEEE 802.3az Energy Efficient Ethernet, IEEE 802.3ad and 802.1AX link aggregation, IEEE 802.1Q VLAN tagging, IEEE 802.1P priority, IEEE 802.1Qaz Enhanced Transmission Selection, IEEE 802.1Qbb Priority Flow Control, IEEE 802.1Qbg, and IEEE 1588v2 Precision Time Protocol. Supports jumbo frames up to approximately 9.6 KB.
- Cables and Transceivers: Compatible with supported 25GbE SFP28 transceivers, direct-attach copper (DAC) cables, and active optical cables (AOC). Transceivers and cables are not confirmed included unless specifically shown in the package contents.
- Operating System Compatibility: Supports Windows 11 and Windows 10 64-bit, Windows Server 2012/2012 R2, 2016, 2019, 2022, and 2025, as well as compatible Linux distributions including RHEL and CentOS, FreeBSD, VMware, and other supported Linux kernel-based systems. Driver installation may be required. Supports OpenFabrics Enterprise Distribution (OFED) and OpenFabrics Windows Distribution (WinOF-2).
- Compatible Adapter Reference: The CX4121A is described by its seller as an alternative to the Mellanox MCX4121A-ACAT adapter. It uses the Mellanox ConnectX-4 Lx MT27711A0 controller. This listing identifies the card by its CX4121A model reference and does not claim that the physical card was manufactured or branded by Mellanox.
- Package Contents: 1x Dual-Port 25GbE SFP28 PCIe Network Adapter.
CX4121A 2X 25GbE SFP28 Interface Inteligent RDMA Ethernet Adpater
CX4121A is a dual 25GbE SFP28 fiber-ports intelligent RDMA Ethernet adapter, designed for seamless networking, clustering and storage applications. Built to the PCI Express Gen 3.0 standard with a PCIE x8 bus interface, it delivers a total bandwidth of 64Gb/s, ensuring both SFP28 fiber ports achieve 25GbE throughput simultaneously. Powered by the high-performance Mellanox ConnectX-4 Lx EN MT27711A0 intelligent converged Ethernet controller, it provides a cost-effective and flexible Ethernet solution for Web 2.0, cloud, data analytics, database and storage platforms.
ATTENTION: The LinksTek CX4121A serves as a drop-in alternative to the MCX4121A-ACAT for server applications.
For Data Center & Server
For Desktop PC
For Personal NASTechnical Specifications:
Mellanox ConnectX-4 Lx EN 2x 25Gb/s Ethernet Controller
IEEEE 802.3 by 25Gb/s Ethernet
Windows 11, 10, Windows Server & Linux
SFP28 25GbE Transcievers
25GbE SFP28 DAC Cables
SFP28 25GbE AOC Cables
PCIE X8 Interface, PCIE X8, X16 Slot
Full Height PC & Slim PC
Full Height & Low Profile Bracket
CX4121A is a dual 25GbE SFP28 fiber-ports intelligent RDMA Ethernet adapter, designed for seamless networking, clustering and storage applications. Built to the PCI Express Gen 3.0 standard with a PCIE x8 bus interface, it delivers a total bandwidth of 64Gb/s, ensuring both SFP28 fiber ports achieve 25GbE throughput simultaneously. Powered by the high-performance Mellanox ConnectX-4 Lx EN MT27711A0 intelligent converged Ethernet controller, it provides a cost-effective and flexible Ethernet solution for Web 2.0, cloud, data analytics, database and storage platforms. It supports I/O virtualization via ConnectX-4 Lx EN SR-IOV technology, offering dedicated adapter resources with guaranteed isolation and protection for virtual machines, helping data center administrators improve server utilization efficiency. It supports overlay networks through advanced hardware offloading engines for NVGRE, VXLAN and GENEVE, allowing data center operators to achieve native performance in modern network architectures. Additionally, it supports RDMA over Converged Ethernet (RoCE), delivering efficient low-latency, high-performance RDMA services over Layer 2 and Layer 3 networks, which greatly enhances the performance of storage applications.
Ethernet Specifications:
Supports IEEE 802.3by, 25 Gb/s; IEEE 802.3ae 10Gb/s; IEEE 802.3az Energy Efficient Ethernet;
IEEE 802.3ap; IEEE 802.3ad; 802.1AX; IEEE 802.1Q. 802.1P VLAN tags and priority; IEEE 802.1Qaz;
IEEE 802.1Qbb; IEEE 802.1Qbg; IEEE 1588V2; Support Jumbo frame (9.6KB).
Compatible System:
Support plug and play on Windows 11, 10 64bit and Windows Server 2012, 2012R2, 2016, 2019, 2022, 2025 64bit.
Compatible with RHEL, CentOS, FreeBSD, VMware and other Linux kernel-based systems.
Package List: 1X CX4121A; 1X Low Profile Bracket
ATTENTION: The LinksTek CX4121A serves as a drop-in alternative to the MCX4121A-ACAT for server applications.
