Amazon.com: CERRXIAN Dual Port Gigabit Ethernet PCI Express PCI-E 1x Slot Network Card NIC 10/100 / 1000 Mbps with Low Profile Bracket for Desktop PC : Electronics
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10Gb PCI-E NIC Network Card for Intel X550-T2, Dual RJ45 Port, with Intel Intel X550 Controller, 10G PCI Express LAN Adapter Support Windows Server/Linux/VMware - Newegg.com
StarTech.com 5G PCIe Network Adapter Card - NBASE-T PCI Express Network Interface Adapter 5GbE Multi Gigabit Ethernet LAN 4 Speed NIC | Five Star Office Supply
Best Buy: TP-Link 10/100/1000 PCI Express Network Card Green TG-3468
Delock Products 66216 Delock Express Card > Gigabit LAN