Although there are hundreds of parts to a Video Card, we will only cover the main ones. The ones we cover will give you an idea of how the Video Card can be regarded to as a mini-system, which has many of the components that the computer has itself. This is one of the reasons that it can usually be the one of the more expensive parts of a computer.

The image below shows ATI's Raedon Video Card, with the main components highlighted. Below the image, there will be descriptions of the individual parts to help you understand the Video Card better.

Similar to the computer's CPU, the GPU processes the information that the Video Card needs in order to display the image on the monitor. The GPU has three typical functions. They are:

• Co-processor designed to take the load off the CPU. With today's complex images, a processor created especially for video is needed to help the computer run faster, and to create more life-like images.
• Used as a Graphics Accelerator. This helps the video card to render the graphics faster, based on the commands sent from the CPU.
• Frame Buffer: Controls the memory on the Video Card. It controls when the information will be sent to the Monitor.

The fastest GPU to date, nVidia's Geforce3 is a step ahead of the competition.
© nVidia Corp., 2001

The Memory is a very important part of a Video Card. In 2D, it stores the information needed to render images, such as the color of every individual pixel. In 3D programs and games, it has to hold a 3D image. This means that it has to hold depth, textures as well as lighting, which takes up much more memory. On most Video Cards, it even has to hold parts of the 3D images that are hidden, usually because they are covered by another object in front of it.

Video Card Memory

Memory is keeping the Video Card development back, because memory technology has not advanced as fast as other technologies used by the Video Card, such as the GPU. A new way of image rendering has been developed to limit the performance impact of the memory bottleneck. This topic is covered in the Tile Rendering page of the Display section.

The Accelerated Graphics Port Connector connects the Video Card to the rest of the computer. AGP allows the Video card to access the system memory without having to go through the CPU, which improves video performance on computers. It allows the CPU to perform other tasks while the Video Card takes information from the system memory.

The Display Connector connects the Video Card to the Monitor. All the data that has finished being processed by the GPU and is ready to be sent to the monitor as an image is sent through here. Note: CRT Monitors and LCD Monitors use different inputs. Most Video Cards work with only CRT Monitors. Some work with LCD Monitors, but they are not very powerful.