Note that this driver says "Series." That is important.

To install the driver for the Realtek PCIe GBE Family Controller Series v2.64, follow these steps:

Deep Dive: The Realtek PCIe GbE Family Controller (v2.64) – Why This Driver Still Matters

How does the Realtek PCIe GBE Family Controller v2.64 compare to its competitors (Intel I219-V or Killer E2500) and older Realtek drivers?

Even with a stable driver like v2.64, issues can arise. Here are solutions to the most frequent complaints.