+(1) 408-943-8000
Save 12%
  • Chelsio T520-LL-CR 10 Gigabit Ethernet Adapter Card - Part ID: T520-LL-CR

Chelsio T520-LL-CR 10 Gigabit Ethernet Adapter Card - Part ID: T520-LL-CR

2-port Low Latency Low Profile 1/10GbE Unified Wire Adapter with PCI-E x8 Gen 3, 32K conn. Direct Attach


20 lbs
Ships within 3-5 Days



Availability In stock



High Performance, Dual Port 10GbE Unified Wire Adapter

Enables TCP, UDP, ISCSI, iWARP and FCoE Offload over Single Unified Wire with SR-IOV, EVB/VNTag, DCB


Chelsio’s T520-LL-CR is a dual-port, ultra-low latency 10 Gigabit Ethernet (10GbE) Unified Wire adapter with a PCI Express 3.0 host bus interface, optimized for financial and HPC applications. The T520-LL-CR is also a Best-in-Class 10GbE interconnect solution for cloud computing, virtualization, storage, and other data center applications.

The fifth generation Teminator 5 (T5) technology from Chelsio provides the highest 10GbE performance in the industry and dramatically lowers hostMsystem CPU communications overhead with on-board hardware that offloads TCP/IP, iSCSI, FCoE and iWARP RDMA processing from the host system and frees up host CPU cycles for other applications. As a result, the system benefits from higher bandwidth, lower latency, and reduced power consumption.

The Unified Wire Solution

The T520-LL-CR enables a unified wire for LAN, SAN, and cluster traffic, made possible by the high bandwidth and low latency characteristics, combined with storage and cluster protocols operating over Ethernet (iSCSI, FCoE, and iWARP). T5 based adapters such as the T520-LL-CR support both file and block based storage protocols and are ideal for building high performance SAN and NAS solutions. With both iSCSI and FCoE offload, FC applications can run natively over Ethernet, while taking advantage of its performance benefits and economies of scale. T5 also offers an ultraMlow latency RDMA over Ethernet (iWARP) interface, making the T520-LL-CR a competative drop-in replacement for InfiniBand in high performance computing applications. It is supported in the same standard software distributions and allows running IB applications unmodified.

T520-LL-CR integrates a fullMfledged hardware Traffic Manager for robust flow control, traffic management, and predictable QoS.

The adapter’s two ports and IEEE 802.3ad link aggregation, and port-to-port and adapter-to-adapter failover features are ideal for critical network applications that require redundancy and high-availability capabilities.

T520-LL-CR Ethernet-only unified networking reduces the data center’s cost in adapters, cables, switches, rack space, power, equipment spares, management tools, planning, installation and operation.


  • PCI Express Gen3 x8
  • Ultra Low Latency
  • Supports Up to 1M Connections
  • Full TCP and UDP offload
  • Full iSCSI, FCoE offload
  • Full iWARP RDMA offload
  • Full NAT offload
  • EVB, Flex10, VNTag
  • Integrated media streaming offload
  • HW based firewall in the cloud
  • Traffic filtering & management
  • Software Compatible with T4


Data-Center Networking

  • Scale up servers and NAS systems
  • Link servers in multiple facilities to synchronize data centers
  • Consolidate LAN, SAN, and cluster networks

Cloud Computing

  • Virtualization features to maximize cloud scaling and utilization
  • Runs InfiniBand, Fibre Channel apps unmodified on Ethernet
  • Cloud ready functional and management features
  • QoS and Traffic management

Networked Storage

  • Enable high performance NAS systems and Ethernet-based IP SANs
  • Develop shared-storage systems providing both file- and block-level services

High Performance Computing

  • Ultra-low latency Ethernet
  • Increase cluster fabric bandwidth
  • Deploy Ethernet-only networking for cluster fabric, LAN, and SAN

Technical Specification

Host Interface

  • PCI Express Gen 3 x8
  • MSI-X, MSI and support for legacy pin interrupts

High Performance RDMA

  • Low latency and line rate bandwidth
  • Enhanced RDMA primitives
  • iWARP support on Linux OFED
  • Support for Atomics and Immediate Data
  • Microsoft Network Direct support
  • Supported Transport for SMB-Direct in Microsoft Windows Server 2012

UDP/IP & Multicast Offload

  • UDP Sockets API offload
  • Low user-to-user latency
  • Multicast replication on ingress or egress


  • 128 Virtual and 8 Physical functions
  • 144 port virtual switch
  • EVB, VEPA, Flex10, VNTag
  • 512 virtual MAC addresses
  • Offload 802.1 Qbg/h


  •  Full HBA FCoE (Initiator or Target)
  • Open-FCoE Offload (Initiator)
  • CRC32 offload generation & verification
  • Ingress & Egress ACL (Access Control List)
  • T10 DIF/DIX support


  • Full iSCSI initiator and target mode stack
  • CRC32 offload generation & verification
  • iSCSI proxy switching based on SCSI CDB
  • Full HBA offload
  • T10 DIF/DIX support

TCP/IP Full Offload

  • Full TCP implementation including IPv4 & IPv6
  • Microsoft Chimney support
  • Extensive RFC compliance, fully featured stack
  • Full TCP Proxy between any set of connections
  • VLAN support up to 4096 VLAN IDs
  • Load balancing and Fail-over capabilities

Stateless Offloads

  • TCP/UDP checksum offload for IPv4 & IPv6
  • TSO, LSO, and GSO for IPv4 & IPv6
  • VLAN filtering, insertion & extraction
  • Line rate packet filtering and attack protection
  • Fine granularity time stamping (down to 2ns)
  • Ethernet Routing (packet header rewrite)
  • Packet Tracing and Packet Sniffing


  • IEEE 802.3ae (10 GbE)
  • IEEE 802.3az (Energy Efficient Ethernet)
  • IEEE 802.3z (1 GbE)
  • IEEE 802.1P priority
  • IEEE 802.1Q VLAN tagging
  • IEEE 802.1Qbg EVB/VEPA
  • IEEE 802.Qhn VNTag
  • IEEE 802.3x flow control
  • IEEE 802.3ad load-balancing and failover
  • Ether II and 802.e encapsulated frames
  • Multiple MAC addresses per interface
  • Jumbo Frames up to 9.6Kbytes

Physical and Environmental

  • Dimensions without bracket: 6.6 in. x 2.7 in. or 16.76 cm x 6.88 cm
  • Operating Temp: 0 to 55ºC or 32 to 131ºF
  • Operating Humidity: 5 to 95%
  • Airflow: 200 lf/m


  •  1-year limited hardware warranty – free repair or replacement for faulty hardware due to Chelsio defect or failure.
  • Extended warranty to 3 years can be purchased within first year.
  • 30 days free technical support, software maintenance & upgrades with the purchase of any Chelsio adapter or software product.

Ordering Info

Model: T520-LL-CR
Physical Interface: 10GBASE-SR or LR*Connector: LC DuplexMedia: MMF or SMF


SM10G-SR: 10G short-reach SFP+ optic module
SM10G-LR: 10G long-reach SFP+ optic module
SRCABLE3M: Fiber optic cable, 10GBASE-SR, 3M
LRCABLE3M: Fiber optic cable, 10GBASE-LR, 3M
TAPCABLE1M: Twinax passive cable, 1M
TAPCABLE3M: Twinax passive cable, 3M
TAPCABLE5M: Twinax passive cable, 5M


Write your own review

You're reviewing: Chelsio T520-LL-CR 10 Gigabit Ethernet Adapter Card - Part ID: T520-LL-CR

Customer Reviews

There are no reviews for this product yet.

Supermicro Partner
Memory usage: real: 23592960, emalloc: 23261400
Code ProfilerTimeCntEmallocRealMem