TheTechLounge - Graphics Cards Tutorial

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Graphics Cards Tutorial
A graphics card (also known as a video adapter or video card)is a card that plugs into your computer so your computer can communicate with the monitor. It is an essential part of your computer. There are many different types of graphics cards. Most graphics cards conform to IBM or VESA standards. Most graphics cards convert digital signals to analog. This is not true on laptops. Most laptop displays are digital.

Graphics cards have several different modes that they will operate under. The two basic categories of video modes are text and graphics. You'll see these two different modes when you boot up your computer. At the beginning of the boot up you see a black screen with white text on it. At this point your graphics card is in text mode. When the Windows splash screen appears, you're now in graphics mode. Different resolutions are available in both text and graphics mode. The lower the resolution the more colors a monitor can display.

Look at your monitor's screen very closely and you'll see that everything is made up of tiny little dots. These dots are called pixels. Each pixel has a color. On some screens pixels can be any of 256 colors. On some screens the pixels can be one of 16.8 million different shades of color. The human eye can only see about 10 million different colors so 16.8 million colors are more than enough. The graphics card tells the individual pixels what color they should be.

Modern graphics cards have their own memory. This frees up the computer's RAM. The computer's RAM doesn't have to store displays. Most adapters have their own graphics coprocessor allowing it to perform graphics calculations. These adapters are called graphics accelerators.

Graphics cards first appeared on the scene way back in August 1981. They were monochrome and typically text only. They were usually green or white text on a black background. A lot of times the graphics card had a printer port on it since the printer would print the same data shown on the screen. Color appeared with the 4 color Hercules Graphics Card (HGC), followed by the 8 color Color Graphics Adapter (CGA) followed by the 16 color Ehanced Graphics Adapter (EGA).

IBM introduced the Video Graphics Array (VGA) in 1987. VGA supported up to 256 colors with resolutions up to 720x400. VGA was analog. Formats preceeding VGA were digital.

Finally VGA gave way to Super Video Graphics Array (SVGA). SVGA was based on VGA but all was not peaches and cream. Each card manufacturer added resolutions and increased color depth in different ways. Eventually the Video Electronics Standards Association (VESA) came up with a standard that provided up to 16.8 million colors and 1280x1024 resolution.

Now that graphics cards have an industry standard you have a choice of a wide variety of cards to choose from. When choosing your card be advised that there are 3 different ways your card can connect to your computer. The 3 different ways are through an Industry Standard Architecture (ISA) slot, a Peripheral Component Interconnect (PCI) slot or an Accelerated Graphics Port (AGP). Most graphics cards purchased today will use the AGP port.