---
product_id: 13667130
title: "CHELSIO COMMUNICATIONS T520-SO-CR 2-Port Low Profile 1/10GbE Server Offload Adapter with PCI-E x8 Gen 3, SFP+ Connector"
brand: "chelsio communications"
price: "¥37783"
currency: JPY
in_stock: true
reviews_count: 3
category: "Chelsio Communications"
url: https://www.desertcart.jp/products/13667130-chelsio-communications-t520-so-cr-2-port-low-profile-1
store_origin: JP
region: Japan
---

# 10GbE ultra-fast connectivity PCI-E x8 Gen 3 high bandwidth Dual-port SFP+ for versatile networking CHELSIO COMMUNICATIONS T520-SO-CR 2-Port Low Profile 1/10GbE Server Offload Adapter with PCI-E x8 Gen 3, SFP+ Connector

**Brand:** chelsio communications
**Price:** ¥37783
**Availability:** ✅ In Stock

## Summary

> ⚡ Power your data center with speed and versatility — don’t get left behind!

## Quick Answers

- **What is this?** CHELSIO COMMUNICATIONS T520-SO-CR 2-Port Low Profile 1/10GbE Server Offload Adapter with PCI-E x8 Gen 3, SFP+ Connector by chelsio communications
- **How much does it cost?** ¥37783 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/13667130-chelsio-communications-t520-so-cr-2-port-low-profile-1)

## Best For

- chelsio communications enthusiasts

## Why This Product

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

## Key Features

- • **Blazing 10GbE Speeds:** Experience lightning-fast data transfer with dual 10GbE ports, perfect for demanding cloud and HPC workloads.
- • **Compact Low Profile Design:** Fits perfectly in space-constrained servers without compromising performance or expandability.
- • **Unified Wire Protocol Support:** Seamlessly run TCP, RDMA, iSCSI, FCoE, NVMe-oF & more concurrently on a single cable.
- • **Next-Gen PCI-E x8 Gen 3 Interface:** Maximize throughput and minimize latency with cutting-edge PCI-E Gen 3 connectivity.
- • **Optimized for Virtualization & Storage:** Boost your data center efficiency with advanced offload capabilities tailored for virtualization and storage networks.

## Overview

The Chelsio T520-SO-CR is a dual-port 1/10GbE low profile server offload adapter featuring PCI-E x8 Gen 3 and SFP+ connectors. Designed for high-performance data centers, it supports a unified wire architecture enabling simultaneous TCP, RDMA, iSCSI, FCoE, NVMe-oF, and more. Ideal for storage, cloud, HPC, and virtualization environments, it delivers robust throughput and advanced offload capabilities in a compact form factor.

## Description

2-port Low Profile 1/10GbE Server Offload Adapter with PCI-E x8 Gen 3, Server Offload. SFP+ connector.

Review: FreeNAS server - it just works - I used this with a DAC cable to connect my FreeNAS server to the network. Install, boot, it just works. Perfect!
Review: Does not work as advertised - Good: Has a good reputation for performance, working well with FreeBSD right out of the box. Bad: In my case, at least, that reputation is unfounded. Docs state specifically that this card works with FreeBSD 10.3-STABLE, which is what my FreeNAS installation is running on. Installed the card, booted up, system recognized the card but driver refused to load. Several hours of research and tweaking were fruitless. Contacted Chelsio tech support. They responded promply. After e-mail exchange, they told me that recent firmware mods no longer support FreeBSD 10, the minimum is now ver. 12.0. Upgrading is not an option for me; FreeNAS will not support 12.0 until later this year. Chelsio supplied a set of patches they claimed would allow use on 10.3. I was and am dubious about rebuilding a critical driver with a set of patches which cannot have been thoroughly tested, but after considerable effort I managed to compile from source with patches applied. Patched driver still refused to load. Gave up, returned the card, and bought an older model Chelsio card on eBay known to work with my version of FreeBSD/FreeNAS. Bottom line: It's possible that I could have made this card work, eventually. The bottom line, however, is that I shouldn't have to. Chelsio made changes to their card that broke an allegedly supported release, and didn't backport their 10.3 driver to match. I need this 10Gb segment online, and I'm uncomfortable with tinkering with a critical driver that is claimed to, and should, work right out of the box. I have just enough faith left in Chelsio to try their S320E card, even if I take a bit of a performance hit. If that doesn't work out, I guess I'll buy an Intel card like I probably should have done in the first place. Two stars, mainly because Chelsio support was fast and professional.

## Features

- 10GbE Unified Wire Adapters for Offloaded TCP, RDMA(iWARP), iSCSI, FCoE, DPDK, NVMe-oF, OvS Offload, Packet Classification & Filtering, Virtualization and more
- The Terminator series of Adapters enable a unified fabric over a single wire by simultaneously running all Protocols Concurrently
- Optimized for storage, cloud computing, HPC, virtualization and other datacenter networking applications

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B00FAU898K |
| Best Sellers Rank | #629 in Internal Computer Networking Cards |
| Brand | Chelsio Communications |
| Customer Reviews | 4.4 4.4 out of 5 stars (10) |
| Date First Available | September 19, 2013 |
| Hardware Platform | Linux;Windows;FreeBSD;MacOS;Illumos;XenServer;vSphere ESXi |
| Is Discontinued By Manufacturer | No |
| Item Dimensions LxWxH | 6.6 x 1 x 2.71 inches |
| Item Weight | 6 ounces |
| Item model number | T520-SO-CR |
| Manufacturer | Chelsio Communications, Inc |
| National Stock Number | 0 |
| Product Dimensions | 6.6 x 1 x 2.71 inches |
| Series | T520-SO-CR |

## Product Details

- **Brand:** Chelsio Communications
- **Compatible Devices:** Desktop
- **Data Transfer Rate:** 10240 Megabits Per Second
- **Global Trade Identification Number:** 00897709002738
- **Hardware Interface:** Ethernet
- **Item Weight:** 0.38 Pounds
- **Manufacturer:** Chelsio Communications, Inc
- **UPC:** 897709002738

## Images

![CHELSIO COMMUNICATIONS T520-SO-CR 2-Port Low Profile 1/10GbE Server Offload Adapter with PCI-E x8 Gen 3, SFP+ Connector - Image 1](https://m.media-amazon.com/images/I/61xzRHH9SML.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ FreeNAS server - it just works
*by R***B on April 2, 2020*

I used this with a DAC cable to connect my FreeNAS server to the network. Install, boot, it just works. Perfect!

### ⭐⭐ Does not work as advertised
*by R***. on July 1, 2020*

Good: Has a good reputation for performance, working well with FreeBSD right out of the box. Bad: In my case, at least, that reputation is unfounded. Docs state specifically that this card works with FreeBSD 10.3-STABLE, which is what my FreeNAS installation is running on. Installed the card, booted up, system recognized the card but driver refused to load. Several hours of research and tweaking were fruitless. Contacted Chelsio tech support. They responded promply. After e-mail exchange, they told me that recent firmware mods no longer support FreeBSD 10, the minimum is now ver. 12.0. Upgrading is not an option for me; FreeNAS will not support 12.0 until later this year. Chelsio supplied a set of patches they claimed would allow use on 10.3. I was and am dubious about rebuilding a critical driver with a set of patches which cannot have been thoroughly tested, but after considerable effort I managed to compile from source with patches applied. Patched driver still refused to load. Gave up, returned the card, and bought an older model Chelsio card on eBay known to work with my version of FreeBSD/FreeNAS. Bottom line: It's possible that I could have made this card work, eventually. The bottom line, however, is that I shouldn't have to. Chelsio made changes to their card that broke an allegedly supported release, and didn't backport their 10.3 driver to match. I need this 10Gb segment online, and I'm uncomfortable with tinkering with a critical driver that is claimed to, and should, work right out of the box. I have just enough faith left in Chelsio to try their S320E card, even if I take a bit of a performance hit. If that doesn't work out, I guess I'll buy an Intel card like I probably should have done in the first place. Two stars, mainly because Chelsio support was fast and professional.

### ⭐⭐⭐⭐⭐ The best 10G card for Linux systems
*by D***D on June 17, 2020*

Would buy it again , package came in a very good condition this time .

---

## 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.jp/products/13667130-chelsio-communications-t520-so-cr-2-port-low-profile-1](https://www.desertcart.jp/products/13667130-chelsio-communications-t520-so-cr-2-port-low-profile-1)

---

*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-01-31*