A+: Installing Network Interface Cards

Although many recent computers include a 10/100 or 10/100/1000 Ethernet port or a Wireless Ethernet (WLAN) adapter, you often need to install a network interface card (NIC) into a computer you want to add to a network.

PCI, PCI Express

To install a Plug and Play (PnP) network card, follow this procedure:

  • Turn off the computer and remove the case cover.
  • Locate an available expansion slot matching the network card’s design (most use PCI, but some servers and workstations might use PCI-X or PCI Express).
  • Remove the slot cover and insert the card into the slot. Secure the card in the slot.
  • Restart the system and provide the driver disk or CD-ROM when requested by the system.
  • Insert the operating system disc if requested to install network drivers and clients.
  • The IRQ, I/O port address, and memory address required by the card will be assigned automatically.
  • Test for connectivity (check LED lights, use a command such as ping, and so on), then close the computer case.


Although USB network adapters are also PnP devices, you normally need to install the drivers provided with the USB network adapter before you attach the adapter to your computer. After the driver software is installed, the device will be recognized as soon as you plug it into a working USB port.

Most USB network adapters are bus powered. For best results, they should be attached to a USB port built into your computer or to a self-powered hub. Some adapters support USB 2.0, which provides full-speed support for 100BASE-T (Fast Ethernet) signal speeds.

If you are using a wireless USB adapter, you can improve signal strength by using an extension cable between the adapter and the USB port on the computer. Using an extension cable enables you to move the adapter as needed to pick up a stronger signal.  Standard USB extension cables can reach up to 5 meters(16') without an intervening powered hub.

PC Card/CardBus

PC Card network adapters work with both the original 16-bit PC Card slot and the newer 32-bit CardBus slot. However, CardBus cards work only in CardBus slots.   Both PC Card and CardBus cards are detected and installed by built-in support for these adapters in Windows 2000 and newer versions.  Some PC Card and CardBus network adapters often require that a dongle be attached to the card to enable the card to plug into a network port.

Configuring Network Interface Cards

Although PCI, USB, PC Card, and CardBus network adapters as well as integrated adapters support PnP configuration for hardware resources, you might also need to configure the network adapter for the type of media it uses, for the speed of the connection and, with Wireless Ethernet adapters, the security settings that are used on the wireless network.

Hardware Resources

Typical network interface card hardware resource settings include IRQ and I/O port address range.  If the workstation is a diskless workstation, a free upper memory address must also be supplied for the boot ROM on the card. A few older network cards also use upper memory blocks for RAM buffers; check the card’s documentation.

Media Type

Most recent Ethernet cards are designed to use only UTP Category 3 or greater network cabling. However, some older cards were also designed to use 10BASE5 (Thicknet) or 10BASE2 (Thinnet) cabling. Cards that are designed to use two or more different types of cabling are known as combo cards, and during card configuration, you need to select the type of media that will be used with the card. This option is also known as the Transceiver Type option. Depending upon the card’s drivers, you might need to make this setting through the card’s command-line configuration program or the card’s properties sheet in Windows Device Manager.

Some network adapters designed for use with UTP cable can automatically sense when the cable is not connected. Windows XP might display an icon in the system area to indicate when a cable is not connected to a network adapter. To enable notification, open the Network Connections window, right-click the connection, select Properties, and make sure the option Show Icon in Notification Area When Connected is enabled.


If the hardware in use on an Ethernet, Fast Ethernet, or Gigabit Ethernet network permits, you can configure the network to run in full-duplex mode. Full-duplex mode enables the adapter to send and receive data at the same time, which doubles network speed over the default half-duplex mode (where the card sends and receives in separate operations). Thus, a 10BASE-T-based network runs at 20 Mbps in full-duplex mode; a 100BASE-T-based network runs at 200 Mbps in full-duplex mode; and a 1000BASE-T-based network runs at 2,000 Mbps in full-duplex mode.

To achieve full-duplex performance on a UTP-based Ethernet network, the network adapters on a network must all support full-duplex mode, be configured to use full-duplex mode with the device’s setup program or properties sheet, and a switch must be used in place of a hub.