Video Card (VGA)

A video card is used to process images so they can be displayed on your monitor. A good video card can make a big difference in the quality of your graphics, so this is particularly important if you play games or work with photography and video.

Definition

A video card connects to the motherboard of a computer system and generates output images to display. Video cards are also referred to as graphics cards. Video cards include a processing unit, memory, a cooling mechanism and connections to a display device.

Functions

For relatively low-end computer systems, the ability to create output images can be integrated into the motherboard or central processing unit (also called CPU). However, if you want to watch movies or play games on your computer (and who doesn't, at least once in a while?), a dedicated video card greatly improves the quality of the graphics. For serious gamers, a high-quality video card may just be the most important part of the computer system - it's a must for rendering 3D graphics in particular.

A video card is a printed circuit board (like a motherboard) and contains its own processing unit and memory. It is like a kind of computer in itself. This essentially takes the load off the motherboard's CPU and memory to process images. The processing unit on a video card is referred to as a graphics processing unit (GPU). This is very similar to a CPU, but its design is optimized to work with images. The memory on a video card is very similar to the regular random-access memory (or RAM) on a motherboard. A video card connects to the motherboard of a computer system using a slot, typically an Accelerated Graphics Port (AGP) or a Peripheral Component Interconnect Express (PCIe) connection.

Video card with the major components labeled

High-performance video cards generate a lot of heat. Video cards therefore need to employ heat sinks, which consist of metal strips to distribute the heat evenly and dissipate the heat into the surrounding air. A heat sink is often located right on top of the GPU. Sometimes a fan is added for additional cooling.

Video card with heat sink and cooling fan