While a simple driver download link is useful, the "interesting" context around the lies in its history, its ubiquity, and the technical quirks that make it one of the most recognizable names in networking hardware.
Windows 10 includes a built-in (“inbox”) driver for the RTL8139/810x family. When a clean installation detects a PCI-E device with matching hardware IDs (e.g., PCI\VEN_10EC&DEV_8139 ), Windows automatically loads rt640x64.sys or the legacy Rtnic64.sys . For most users, this “plug and play” functionality is sufficient for basic internet access and file sharing. realtek rtl8139 driver 810x family pci-e gigabit windows 10
Are you experiencing a in Device Manager, or is the adapter just not showing up at all? While a simple driver download link is useful,