CX4121A 2X 25GbE SFP28 Interface Inteligent RDMA Ethernet Adpater 

1. CX4121A is a dual 25GbE SFP28 fiber port intelligent RDMA Ethernet adapter with a PCIE Gen 3.0 x8 interface. Based on the Mellanox ConnectX-4 Lx EN MT27711A0 converged Ethernet controller, it provides a cost-effective and flexible Ethernet solution for Web 2.0, cloud, data analytics, database, and storage platforms.
2. Ethernet Controller: Mellanox ConnectX-4 Lx EN MT27711A0；Bus Interface: PCIE 3.0 x8; Ethernet Speed: 2x 25GbE; Connector Type: 2x SFP28 Fiber Ports; Remote Boot: RoCE, PXE, iSCSI; Supports RDMA over RoCE; Support I/O Virtualization and SR-IOV; Support Overlay Networks by providing advanced NVGRE, VXLAN and GENEVE.
3. 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).
4. PCIE Gen 3.0 Standard, 8Gb/s Per Lane. PCIE x8 Interface, 64Gb/s Bandwidth Totally, Ensure 2x SFP28 Fiber Ports archive 25GbE simultaneously. Auto-negotiates to PCIE X8, X4 Lane. Auto-switch to PCIE Gen 3.0, Gen 2.0. Support MSI/MSI-X mechanisms.
5. 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.
6. Support Open Fabrics Enterprise Distribution (OFED) and Open Fabrics Windows Distribution (WinOF-2). Will compatible with SFP28 transceivers, SFP28 DAC cables and SFP28 AOC cables with PAM4 ethernet links.
7. ATTENTION: The LinksTek CX4121A serves as a drop-in alternative to the MCX4121A-ACAT for server applications. 

Technical Specifications:

A.  1. Select the Mellanox ConnectX-4 Lx EN MT27711A0 converged ethernet controller, provide 2X 25GbE ports on Desktop PCs will reduce the power consumption. 2. Will works on Intel, ARM and AMD platform. 

B.  1. Users will get IEEE 802.3by 25Gb/s max speed on it's data center and desktop PCs. 2. Supports the IEEEE 802.3ae 10GbE and 1GbE standard, do not support 2.5GbE and 5GbE standard. 

C.  1. Plug and play on Windows Server 2025, 2022, 2019, 2016, 2012R2, 2012 systems.2. NO Need to install driver on Windows 11, 10, 8.x 32/64bit systems. 3. Compatible with RHEL, CentOS, FreeBSD, VMware and other Linux kernel systems. 

D.  1. PCI Express X8 interface design, will works on PCIE X8 and X16 LANE slot. 2. PCIE version 3.0 standard, will compatible with PCIE 2.x, 3.x, 4.x and 5.x standard. Provide 64Gbps Bus speed, ensure 2X SFP28 hit 25GbE max speed simultaneously. 

E.  1. Full height bracket mounted on the PCIE nic adapter will supports full height Server or PCs. 2. The Low profile bracket in the package, will works on Slim PCs

F.  1. Support 25GbE and 10GbE standard , when using SFP28 transceivers.2. Support 25GbE or 10GbE only when connected DAC or AOC Cables. 3. CX4121A MUST works with SFP28 transceivers, direct attach twin axial cable ( DAC up to 10meters) and AOC cables. 

 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.