I installed a new TP-Link TX401 10Gb network card in my PC, but the LAN-port LEDs stay off when I connect a cable. Windows Device Manager does not detect the card either, and the TP-Link driver installer says the adapter cannot be found. The motherboard is an ASRock B550M SE WiFi. What should I check before assuming the card is defective?
3 Answers
Start with the basics: install the latest TX401 driver from TP-Link, update the AMD B550 chipset drivers, and check for a newer BIOS/UEFI version. Also inspect the PCIe slot and the card’s contacts for dust or poor seating. The motherboard manual may indicate that another device is sharing or disabling that slot.
Try moving the card to another available PCIe slot, especially if the graphics card is occupying the primary slot. You can also enter the BIOS and change that slot’s PCIe link speed from Auto to Gen 3, save the setting, and completely power off the computer before testing again.
If the driver installer cannot see the adapter and it never appears in Device Manager, the problem is probably hardware detection rather than a Windows driver issue. Test the card in another compatible computer if possible. If it is missing there too, it is likely defective and should be returned or replaced.

I tried installing the driver, but the installer reported that the adapter could not be found. At this point I’m wondering whether the card arrived dead.