Though the procedure for installing different kinds of expansion cards is largely identical, we need to make sure the cards are going in the

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right slots. Unless you are using some pretty dated equipment, your graphics card will have a Peripheral Component Interconnect Express (PCI-E) connection, as will your motherboard. The process is almost identical if you are using the older AGP (Accelerated Graphics Port) interface, though.
On our ASUS P5E-VM DO motherboard, the PCI-E slot is in the yellow rectangle as pictured. Note that one picture is of the empty motherboard from earlier on, and the other shows the graphics card already installed. Refer to your motherboard manual to identify the correct slot, or slots. A motherboard able to run multiple graphics cards may have several PCI-E slots that seem identical, but offer different bandwidths. Its manual will tell you which to use.
Some cards will use smaller PCI-E slots (blue rectangle) than the graphics card (graphics cards send a lot of data back and forth to and from the motherboard so they need the big slots). Others will use PCI slots, which are slowly being replaced by PCI-E, but still going strong. Most current motherboards have a couple or few of each kind for a balance of future-proofing and backwards compatibility.
The Wi-Fi card we are adding to our PC uses a PCI slot. We could use either of the two on our motherboard. Using the one (in the red rectangle) further from the graphics card slot gives us more room to work, and more room for air to get to said card. Graphics cards can be pretty warm, though the nVidia GeForce 8400 GS from eVGA we’re using is on the modest side.