If you cannot find the original VIA driver, Windows 11 has a hidden legacy driver that sometimes works.
Overall Rating: ⭐⭐⭐ (3/5) – Works, but requires manual effort.
The VK-QF9700 is a USB 2.0 to Fast Ethernet adapter based on the Qiao Feng QF9700 chipset (a less common clone of the ADM851x or similar). It’s often found in generic, low-cost USB Ethernet dongles. vk-qf9700 driver windows 11
Do not expect modern Gigabit speeds. The VK-QF9700 is a Fast Ethernet (10/100) chip.
| Connection Type | Theoretical Max | Real-World Speed | | :--- | :--- | :--- | | USB 2.0 (QF9700) | 100 Mbps | 85 - 95 Mbps | | USB 3.0 Gigabit adapter | 1000 Mbps | 300 - 940 Mbps | Use the hardware IDs to search for compatible
Why is my QF9700 so slow? The chip uses the legacy USB 2.0 bus, which shares bandwidth with all USB devices on the same controller. On Windows 11, background system telemetry can also consume small amounts of CPU time that this older chip lacks.
Recommendation: If you are using the adapter for gaming, 4K streaming, or large file transfers on Windows 11, consider upgrading to a USB 3.0 Gigabit adapter (Chipset: Realtek RTL8153 or ASIX AX88179). They cost $15–$20 and require zero manual driver installation on Windows 11. If you cannot find the original VIA driver,
Microsoft significantly tightened driver security in Windows 11 (and Windows 10 1709+). The last official driver for the QF9700 was written for Windows 7 (x86/x64). That driver is not digitally signed for modern Windows kernel requirements.
If you plug in the adapter:
There are three reliable methods to get this driver working. Follow them in order.