---
product_id: 299179111
title: "ConnectX-4 Lx EN Network Adapter (MCX4121A-ACAT)"
brand: "mellanox"
price: "€ 217.10"
currency: EUR
in_stock: true
reviews_count: 1
category: "Mellanox"
url: https://www.desertcart.sk/products/299179111-connectx-4-lx-en-network-adapter-mcx4121a-acat
store_origin: SK
region: Slovakia
---

# 25.6 Gbps blazing throughput Multi-host tech for max ROI PCIe x8 high-speed interface ConnectX-4 Lx EN Network Adapter (MCX4121A-ACAT)

**Brand:** mellanox
**Price:** € 217.10
**Availability:** ✅ In Stock

## Summary

> 🚀 Elevate your network game with Mellanox ConnectX-4 Lx EN – where speed meets smart innovation!

## Quick Answers

- **What is this?** ConnectX-4 Lx EN Network Adapter (MCX4121A-ACAT) by mellanox
- **How much does it cost?** € 217.10 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.sk](https://www.desertcart.sk/products/299179111-connectx-4-lx-en-network-adapter-mcx4121a-acat)

## Best For

- mellanox enthusiasts

## Why This Product

- Trusted mellanox brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **PCIe x8 Interface:** Seamlessly integrates with your server for ultra-low latency and efficient CPU offload.
- • **OCP 2.0 Form Factor:** Future-proof your infrastructure with industry-standard open compute compatibility.
- • **Multi-Host Technology:** Revolutionize your data center with innovative rack designs that slash CAPEX and OPEX.
- • **Virtualization Optimized:** Host more VMs per server with cutting-edge performance in virtualized overlay networks.
- • **Blazing 25.6 Gbps Throughput:** Experience lightning-fast data transfer that accelerates your web and storage performance.

## Overview

The Mellanox ConnectX-4 Lx EN Network Adapter (MCX4121A-ACAT) delivers industry-leading 25.6 Gbps Ethernet throughput with ultra-low latency via a PCIe x8 interface. Designed for Open Compute Project 2.0 compliance, it supports multi-host technology to maximize data center ROI by enabling innovative rack designs and enhanced virtualization performance, making it ideal for high-demand server and storage environments.

## Description

With ConnectX-4 Lx EN, server and storage applications will achieve significant throughput and latency improvements resulting in faster access, real-time response and more virtual machines hosted per server. ConnectX-4 Lx EN for Open Compute Project (OCP) specification 2.0 improves network performance by increasing available bandwidth while decreasing the associated transport load on the CPU especially in virtualized server environments. Moreover, ConnectX-4 Lx EN introduces the multi-host technology, which enables a new innovative rack design that achieves maximum CAPEX and OPEX savings without compromising on network performance.

Review: Israeli made!!!!! - Israeli made!!!!!

## Features

- Open compute project form factor
- Industry-leading throughput and low latency for web access and storage performance
- Maximizing data centers' return on investment (ROI) with multi-host technology
- Smart interconnect for x86, Power, ARM, and GPU-based compute and storage platform
- Cutting-edge performance in virtualized overlay networks

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B011HVAZ78 |
| Best Sellers Rank | #17,258 in Computers ( See Top 100 in Computers ) #38 in Network Cards |
| Brand | Mellanox |
| Built-In Media | Mellanox network adapter |
| Color | Assorted |
| Compatible Devices | Desktop |
| Customer Reviews | 1.0 1.0 out of 5 stars (1) |
| Data Link Protocol | Ethernet |
| Data Transfer Rate | 25600 Megabits Per Second |
| Global Trade Identification Number | 07290107197861 |
| Hardware Interface | PCIE x 8 |
| Item Type Name | ConnectX-4 Lx EN Network Adapter |
| Item Weight | 0.18 Pounds |
| Manufacturer | INGB9 Music Vendor Code |
| Mfr Part Number | MCX4121A-ACAT |
| Model Number | MCX4121A-ACAT |
| Unit Count | 1 Count |

## Product Details

- **Brand:** Mellanox
- **Colour:** Assorted
- **Compatible devices:** Desktop
- **Data link protocol:** Ethernet
- **Hardware interface:** PCIE x 8

## Images

![ConnectX-4 Lx EN Network Adapter (MCX4121A-ACAT) - Image 1](https://m.media-amazon.com/images/I/612n71ocDLL.jpg)

## Questions & Answers

**Q: Can a unifi SFP cable be connected to this card directly?**
A: If you mean the copper SFP28 DAC cable, then yes.  I am currently using that.  For a fiber cable, you need a transceiver.

**Q: Does this come with a low profile adapter?**
A: Yes.

**Q: I have a qnap 873e w/qxg-10g1t add-in. will the mcx4121a-acat 25gigabit ethernet card support this using cat7? what speed could i expect?**
A: This NIC uses SFP28 adaptor.
If you use SFP+ transceiver with 10G base-T, you will get 10G speed

**Q: Does this item ship with both tall bracket and short bracket ? Or only with tall bracket, as in the picture ?**
A: Both

## Customer Reviews

### ⭐ Israeli made!!!!!
*by I***D on 27 July 2021*

Israeli made!!!!!

## Frequently Bought Together

- Mellanox ConnectX-4 Lx EN Network Adapter (MCX4121A-ACAT)
- 10Gtek 25G SFP28 SFP+ SR Transceiver, 25GBase-SR Duplex LC MMF Optical Module for Mellanox MMA2P00-AS, 850nm, DDM, up to 100m
- 10GTEK 25G SFP28 SFP+ DAC Cable - 25GBASE-CR SFP28 to SFP28 Passive Direct Attach Copper Twinax Cable for Cisco SFP-H25GB-CU2M, Ubiquiti UC-DAC-SFP28, Supermicro and More, 2-Meter(6.6ft)

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.sk/products/299179111-connectx-4-lx-en-network-adapter-mcx4121a-acat](https://www.desertcart.sk/products/299179111-connectx-4-lx-en-network-adapter-mcx4121a-acat)

---

*Product available on Desertcart Slovakia*
*Store origin: SK*
*Last updated: 2026-05-19*