Step 11: Graphics card
The first step to installing a graphics card is to remove the metal plate on the back of the case that alligns with the PCI-Express x16 slot. Sometimes you do this by removing a screw, sometimes you need to wiggle it loose until it breaks off. If your video card has a wide cooler, you may need to remove the slot underneath PCI-Express x16 as well.
Now you can slide the graphics card into the PCI-Express x16 slot. On some motherboards slots have a lock that needs to be opened prior to placing the card, and closed again afterwards. In most motherboards, however, the slot works the same way the RAM module slots do. You flip the two clips outwards, and by sliding the video card into place they flip back by themselves.
Once the video card is in its slot, you need to fasten it at the back of the computer case with a screw where you previously removed the metal plate. Some cases have a click system removing the need for a screw.
The last step is connecting extra power cables for more demanding video cards, should it be necessary. These 6- and 8-pin power cables come from the power supply, of course.