- 1). Shut down the computer and unplug the power cord from the outlet. Disconnect the remaining end of the cord from the rear panel of the computer. Turn off the monitor and disconnect it from the rear panel. Unplug any other cords or cables attached to the ports located on the front and rear of the computer.
- 2). Place the computer on a stable work surface, with the rear panel in view. Tilt the computer onto its side, with the left side panel facing upwards. Use the Phillips screwdriver to remove the screws that secure the side panel to the rear panel. Pull the side panel towards the rear of the computer, then lift it free of the computer case.
- 3). Inspect the motherboard and find the PCI slots, located near the rear panel of the computer. Select the desired PCI slot. Remove the retaining screw from the metal plate located next to the PCI slot. Remove the metal plate from the case and set it aside.
- 4). Insert the Ethernet PCI card into the PCI slot. Confirm that the card is fully seated, then use the retaining screw to secure the end of the card to the rear panel of the case.
- 5). Examine the back of the left side panel and locate the tabs near the top and bottom edges. Fit the side panel back into place by inserting the tabs into the slots on the left side of the case. Use the previously-removed screws to secure the side panel in place. Return the computer to its original location.
- 6). Plug the network cable into the Ethernet port on the PCI card. Reconnect the monitor, power cord and any other previously-disconnected cords and cables; Plug the power cord into a wall outlet and turn on the computer. Log into your operating system and insert the card's installation CD into the optical drive. Run the installer application and follow the on-screen instructions.
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