The Atheros AR8131 PCI-E Gigabit Ethernet Controller is a network interface card (NIC) that provides Ethernet connectivity for devices like desktop computers and laptops. It's commonly used in many older systems, especially in desktop motherboards. This controller supports gigabit Ethernet speeds (up to 1000 Mbps) for wired network connections.

The Atheros AR8131 requires a specific driver to function properly on Windows. Without the correct driver, the device may not work correctly, and you may not be able to connect to wired networks.