Find and activate the power off or shut down feature of the operating system installed on the computer. Once the computer has properly shut down, remove the power cable that connects the computer to the wall outlet or surge protector.
Cases have a variety of methods used to open them. Large thumb screws on the back of the system are common, though some types of computer may rely on buttons or hinges to provide access to the internal components.
With the case open, the computer’s expansion slots are exposed. These slots are found toward the lower portion of the motherboard, usually at the back side of the system. These expansion slots, called PCI or PCIe slots, are horizontal and run toward the back of the case. An empty slot is all that is needed to properly install a Wi-Fi network card. Determining which type of slots are present in the computer requires checking the model of computer or motherboard. PCI slots have a divider that creates a smaller area on the right end of the slot, while PCIe slots exhibit the divider on the left.
Once empty slots have been identified, find the right wireless network card that fits the empty slot by looking for what type of connectors the wireless cards use. Models have the connector type listed on the box. If no slot was available inside the computer, some wireless models are capable of using USB slots instead, which provides an easy option for computers that do not have room internally.