It is best to clean the dust off your video card once every four months or so. However, if you notice your computer is getting overheated, you may want to look inside to see if you can spot anything that may be causing it to become too hot. Sometimes it may be a dirty video card.
Use an electrostatic discharge (ESD) wrist strap. Before going into your computer, be safe and use the ESD strap available at most stores where computers or computer parts are sold. This will channel any static electricity you may have picked up to the proper place into the computer and not ruin any possible sensitive parts you may touch. You will need to attach the Velcro part to your wrist and clip on the flexible cords to the frame of your computer. However, be sure this follows the directions of your specific strap.
Slowly remove the video card from its slot. Some video cards that have fans will have a plug to its power source you will need to remove first. Do so gently.
Use a can of compressed air to blow off the dust. Compressed air is available at most stores where computer or computer parts are available. If you have a card with a fan, do the opposite side first with no fan. If it doesn't have a fan at all, do the same thing for both sides. Start to blow air at an angle rather than directly down so the dust blows off of the video card and not just push it farther into the card itself. Do not hold the air button down. Instead, use short bursts of air as you are cleaning.
If applicable, clean the fan side of the video card. Use the compressed air to clean the fan. Hold the blades so they don't spin while you blow short bursts of air into the fan. You should see the dust flying out. Then clean the rest of that side with the canned air.
Put the video card back. Slowly slide the video card back into the computer and reconnect the plug, if any. The plug may be have pinned prongs, so be careful to go in straight so you don't bend the pins.
You can blow the dust off the contacts (the part that touches the motherboard) with the compressed air, but do not touch.