StarTech.com Dual Port 10G PCIe Network Adapter Card, Tehuti TN4010 10GBASE-T & NBASE-T PCI Express Network Interface Adapter 10/5/2.5/1GbE Multi Gigabit Ethernet 5 Speed NIC LAN Card - Network Adapter Card (ST10GSPEXNDP) - network adapter - PCIe 2.0 x8 -

This dual-port 10Gb PCIe network card offers a versatile and low-cost way to deploy 10GbE network connectivity. It adds two copper Ethernet ports to your server or desktop computer and provides Multi-Gigabit Ethernet access to your network at five speeds: 10G, 5G, 2.5G, 1G and 100Mbps.
The 10GBASE-T NIC provides additional bandwidth using your existing Ethernet infrastructure to help reduce the cost of cabling upgrades. The card enables you to connect to 10GBASE-T and NBASE-T equipment at network speeds of: 100Mbps, 1Gbps, 2.5Gbps or 5Gbps over your CAT5e cabling (up to 100 m); 10Gbps over your CAT6 or better cabling (up to 100 m).
The network adapter card adds two Ethernet ports to your workstation through an x8 PCIe 2.X (or higher) slot. It features 10GBASE-T technology, supporting advanced Multi-Gigabit systems, including Cisco campus switches and Aruba Networks access points. The NIC card also supports additional features including 9K Jumbo Frames, Autonegotiation, Auto-MDIX and 802.1q VLAN tagging.
The dual Tehuti TN4010 + Marvell 88X3110 chipset, compliant with IEEE 802.3az, ensures peak operation and reduced power consumption. The decreased consumption minimizes the heat generated to avoid operating temperatures increasing within your server case.