The Peripheral Component Interconnect or PCI slot allows the easy installation of an expansion card such as a wireless card or other device into a desktop computer. PCI is slowly being superseded by PCI Express which is a newer faster standard. Examining the picture to the right of this paragraph we can see at the top two PCI express slots (black) and two PCI slots (beige) below them. The steps required for the installation of either of these types of devices is identical, apart from the obvious difference in slot size and shape, so we shall illustrate the installation of a PCI expansion card, which is still the more commonly found of the two types.
As a first step turn the computer off and remove the cables from its rear marking them or making note of their positions so that they can be plugged back in exactly where where they were initially plugged in. Place the computer onto a table or workbench so that it may be worked on comfortably and remove the sidecovers. Most computer sidecovers are held on by two or three screws on the back of the computer which once removed will allow the side covers to slide off. Once the covers are removed locate an empty PCI slot on the mainboard.
Remove the slot cover on the case that matches the PCI slot you have selected (above left) as the card will slide into the space it covers. Gently slide the wireless card into the PCI slot using firm even pressure on the card so that it is inserted evenly into the slot. Make sure that it is sitting squarely and not at an angle. (above right).
When the card is seated correctly install the slot cover screw as pictured to the right and fasten it down taking care not to overtighten it. If the card has an external antenna screw or slide it onto the card and put the sidecovers back on the machine. Finally, plug the machine back in, referring to your notes where necessary and turn it on. The machine should power up as normal and you should now be ready to move onto the install drivers section relevent to your operating system.
If the computer does not start check the cables that connect to the rear of the PC and double check that everything is exactly where it should be. Also check that the power supply does not have a switch that has been accidentally turned of at some point. If the machine powers up but does not boot remove the card and attempt to start the machine again. If it starts turn it back off, repeat the above process to install the PCI card but try using another slot if one is available.