Let's all be honest with ourselves...the great attraction of our computers is the display. It is what allows us to explore our world and the far reaches of space through our internet connections or play all types of interactive games or catch up on the news or, as I am doing now, write an article. But computers really only speak binary code... ones and zeroes and a screen full of ones and zeroes would not hold our attention for very long. That is where the video or graphics card comes into the picture (if you'll pardon the pun).

It is the job of the graphics card to translate all those ones and zeroes into pictures and words. Exactly how does it do that, you ask? The following is the simplified answer to that question.

The first step is the concept of the Picture (Pix) Element (El) which is most commonly known as a Pixel. The pixel is simply a dot of coloured light whose actual size is determined by the capabilities of the monitor. It is the job of the video card to tell the monitor exactly where to put that tiny dot of light and what colour and brightness the dot should be. In modern video cards it is possible to program more colours than the human eye can see (16 million), a number in the multiple millions of colours with all its possible tints, hues and brightnesses. (My first computer let me see up to a whole 256 colours which demonstrates how far we have come.) Naturally the colour is given to the video card in binary code, as is the information on the location of each coloured pixel.

Consider a typical screen resolution of 1024 (width) X 768 (height). Do the math and that is a possible 786,432 locations for that little dot of light to be placed on the screen. Now consider that every single one of those locations has to be filled with its own particular dot of light. Again all this is done in binary code and each individual location for that pixel is held in memory until the picture changes as you type a sentence or a new picture pops up on your internet connection. Now are you starting to see why video cards need so much memory to play those games with the explosions and alien enemies?

Of course at this point your video display is still blank. That is the second job of the video card, telling the computer's monitor where to put all those dots on the screen. Monitors, however, DO NOT speak binary code; even R2D2 needed C3P0 to translate for him with humans. So all that binary code the graphics card worked so hard to create (with the assistance of the CPU) is now translated into an analog signal and sent to the monitor. LCD and Plasma monitors run into the situation where the video card does not know it doesn't need to translate the binary to analog. The result is binary to analog and then back to binary.

And all that is why when you buy a video card it needs to be the fastest, most powerful card you can fit into your budget. Unless of course you only use your computer to check your e-mail, in which case I have this old card...

Learn more about this author, Robert Heintzman.
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