Realtek no longer offers separate downloads for the RTL8139, but their "Win10 Auto Installation Program" for the PCI-E Ethernet family works perfectly.
Go to a trusted source like Station-Drivers or Realtek’s official site (search for "Realtek PCI-E Ethernet Drivers"). Look for version 10.069 or newer.
Direct filename to look for: Install_Win10_10069_08022024.zip (or similar dated version). realtek rtl8139 driver 810x family pci-e gigabit windows 10
If standard uninstall fails, download RAPR (Driver Store Explorer). Search for any rt640x64, rt8139, or netrt entries and delete them. This nukes old driver remnants.
If you truly have an old RTL8139 card (PCI, not PCI-E) and you need Windows 10: Realtek no longer offers separate downloads for the
Cause: Driver conflict or power management fault. Fix:
If you still see a yellow exclamation mark: Direct filename to look for: Install_Win10_10069_08022024
Use the 810x Family driver from Realtek’s PCI-E Gigabit page. Do not use an old RTL8139-specific driver.
While the RTL8139 (original PCI version) is limited to 100 Mbps, it remains fully functional for web browsing and light streaming. However, on a Gigabit network, the older chip becomes a bottleneck. The PCI-E 810x series, by contrast, can achieve 800–940 Mbps in real-world transfers on Windows 10, provided the driver’s checksum offloading is enabled. Disabling “Large Send Offload” (LSO) sometimes improves stability on buggy router firmware.
One important limitation: neither the RTL8139 nor the 810x family supports IPv6 checksum offloading fully in older hardware revisions. Windows 10’s heavy reliance on IPv6 (for Cortana, Store, and updates) can increase CPU usage slightly—by 2–5%, barely noticeable on modern CPUs.
Before downloading any file, look at your hardware. Open your PC case or check your laptop’s specifications.