What Is a Video Controller?

by Christine Kim

A video controller, often referred to as a video or graphics card, is a key hardware component that allows computers to generate graphic information to any video display devices, such as a monitor or projector. They are also known as graphics or video adapters. Some modern computers do not include video cards, but rather have graphics processing units directly integrated into the computer's motherboard.

Older Video Controllers

A video controller, once more commonly referred to as a video display controller, were used in older models of home-computers during the 1980s; they were also used in some early video game system consoles. Their main function as an integrated circuit in a video signal generator was to produce television video signals in computers or game systems. Although they could generate graphics, older video controller models did not have specialized hardware accelerators that created 2D and 3D images.

Evolution of the Video Controller

Modern video controllers are installed with hardware accelerators that create both 2D and 3D images. They also offer various functions beyond accelerated image rendering, such as TV output and the ability to hook up to several monitors. Although many computers' motherboards are already integrated with graphics processing units, you can disable the integrated graphics chip via the computer's BIOS to install a higher-performance video controller via the accelerated graphics port. For a modern video controller to function properly in a computer, a computer needs to have four essential units: a functioning motherboard, a processor that generates the power that a video controller needs to perform its tasks, enough memory to distribute the images created by the GPU and a screen or monitor to properly display these images.

GPU

As the brain of a computer's motherboard is the CPU, video controllers have their own unique "centers," referred to as the graphics processing unit, although the GPU is also referred to as the visual processing unit. The GPU's specialized electronic circuit is designed specifically to translate data into graphic images and performs complex mathematical calculations in order to do so. GPUs are also embedded into mobile phones and game consoles.

Advanced Video Cards

A modern video controller, more frequently referred to as a video card, are installed into expansion slots onto the motherboard of a computer. The parts of a modern video card include power supply connectors, a cooling fan, a GPU, and typically also have a PCIe interface, Graphics Double Data Rate version 5 memory, a display port, a digital video interface and an HDMI interface. While some video cards have only one port for connection, other advanced cards have multiple ports that connect to additional televisions and monitors. Advanced 3D graphics cards, which are more expensive than the average consumer graphics card, allow consumers to preview modeling viewpoints more fluidly. For example, both AMD Radeon and Nvidia release popular graphics cards used by gamers. At the time of publication, the specs for a high-performance video card made by AMD is the Radeon video card, which has 4GB of memory, 1250 MHz memory clock speed and 320GB per-second memory bandwidth. For graphic artists, many computers come with GPU-accelerated apps, such as Microsoft's DirectX or Nvida's close integration with the Autodesk suite. Rather than utilizing a video card slot, GPU-accelerated programs are integrated into the CPU.

About the Author

Christine Kim has been a writer and editor since 2002, working with Columbia University, Harvard Business School and University of Alabama Press. She holds a Master of Arts in interdisciplinary studies and a Master of Fine Arts in creative writing.

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