Ethernet ports enable a computer to connect to a wired network. On some ASUS computers, the Ethernet port is integrated into the motherboard; on others, a dedicated network card that includes an Ethernet port is installed to an expansion slot on the PC. If the Ethernet port stops working, the computer will stop connecting to wired networks -- but sometimes it's hard to tell if the problem is due to the Ethernet port or something else.
Troubleshooting
Before assuming that the problem is related to the Ethernet port itself, it's important to first rule out other issues that could cause the computer to stop detecting the wired network. If possible, link a different computer to the wired network. If the computer is able to connect to the Internet, then the problem is with the ASUS PC; if not, the problem is with the network equipment or signal. Confirm, via the Network and Sharing Center, that the Ethernet adapter is enabled, then check Device Manager to confirm that the software for the Ethernet adapter is working. Use the search box on the Start menu to search for these two utilities.
Self-Diagnostic
ASUS features an online self-diagnostic tool, available on the official ASUS website. Select a product from the drop-down menu, then follow the onscreen prompts to find the cause of the Ethernet issue. Depending on which ASUS product you own, you may be able to download, install and use a software diagnostic. The following motherboard models can use the ASUS software diagnostic: M4A89GTD PRO, M4A89GTD PRO/USB3, M4A89TD PRO, M4A89TD PRO/USB3 and M4A77TD PRO. Note that these models must be running Windows 7 to use the tool.
Solution
If troubleshooting fails to resolve the problem, replacing the Ethernet card, or installing a new card, may be the only option. Look up your product model on the ASUS website, then review your computer's product specifications. Check whether the computer comes with a dedicated Ethernet card or an integrated Ethernet port, then see which expansion slots the motherboard uses. Laptop motherboards use ExpressCard or personal computer memory card international association; desktop motherboards use peripheral component interconnect, PCI-X or PCI Express. Purchase the appropriate replacement card for your product.
Replacement
Disable the Ethernet adapter in Device Manager before installing the new card to the computer. Check the documentation to see whether you need to install the software for the Ethernet card before installing the card itself. If you're using a laptop computer, you can simply slide the replacement card into the appropriately sized slot on the side of the PC. Desktop computers are more difficult; you must unplug the power cord and remove the case cover to access the expansion slot. Insert the replacement card into the correct slot on the motherboard.
Tags: Ethernet port, Ethernet adapter, Ethernet card, installing card, replacement card, wired network