An Explanation of How a Graphics Card Works

In order to have images appear on your computer screen, you need something that can convert binary data (that's all of those 0's and 1's) into a picture. Computers either have graphics capabilities already built in to do that, or you have to install a graphics card.

For computers that do not already have graphics capabilities, the graphics card is where that translation from binary code to image takes place. A graphics card receives information sent from the processor (CPU) using software applications. The processor is the "central processing unit" (aka CPU or microprocessor).

A graphics card uses four main components to complete its tasks:

*A MOTHERBOARD: A motherboard is what allows all of the parts of a computer to receive electric power and communicate with one another. On most computers, the motherboard has sockets and slots where processors and the system's main memory are stored. It has memory chips and chipsets (which are simply groups of chips) and a clock generator which is a circuit that produces a clock signal. A motherboard has power connectors which receive and distribute electric power from the computer's power supply (usually just an electric cord). Most motherboards also have connectors for input devices for such things as a mouse or keyboard. The graphics card uses the motherboard to receive electric power and to receive data from the computer's processor.

*A PROCESSOR: A processor (aka CPU, microprocessor) is an aptly named chip that processes data. The graphics card uses the processor to decide what to do with a pixel, like what color it should be and where it should be placed in order to make an image on the screen.

*MEMORY: Whether data comes from permanent storage on a hard drive or from other input sources like keyboards, the data goes into random access memory (RAM) where the processor retrieves it. RAM is a temporary storage for data that allows the processor to access the data quickly. It would greatly slow down a computer if the processor had to access the hard drive for every piece of information it needed. The graphics card uses memory to hold information about each pixel (its color and location on the screen) and temporarily stores the final images.

*A MONITOR: Most of us know what the monitor is. It is the piece of the computer you are looking at right now to see this article. A graphics card uses a monitor so that you can see the final result.

A graphics card is a printed circuit board, similar to the motherboard, that is another component that is connected to the computer's motherboard. The connection to the motherboard is how it is powered and how it communicates with the processor. Some graphics cards require more power than a motherboard can provide, so they also connect directly to a computer's power supply.

The graphics card houses its own processor and memory (RAM) and has a Basic Input/Output System chip (BIOS, pronounced "bye-ose") that stores the card's settings and performs diagnostics on the memory at startup. The graphics card processor is called a graphics processing unit (GPU).

The graphics processor (GPU) creates images that it stores in the memory (RAM). The memory connects to a digital-to-analog converter (called the DAC or RAMDAC). As the name suggests, the converter takes the data from the memory and converts it into an analog signal for the monitor which is sends through a cable. The analog output from the RAMDAC goes to the monitor to display the image.

Don't be intimidated; it's really all just a bunch of terms that really are not that difficult to understand. It just takes getting used to the compuer vocabulary.