Graphics Cards

[herme3]

What exactly is the purpose of video/graphics cards in computers? The digital data for a picture is generated in the computer, and it isn't translated into an actual picture until it reaches your monitor. Does the graphics card simply act as extra processing and memory for the image, so the CPU and RAM can focus on the rest of the program? Wouldn't the CPU still have to process the image, to separate it from the rest of the code in the program? Why doesn't it just send the image to the monitor, instead of the graphics card?

[Cap'n Refsmmat]

Graphics cards are highly optimized to do things like shading, transparency, and so on. The processor tells the graphics card "I wand x region shaded with y color with a bit of transparency at coordinate x,y" and then moves on, while the graphics card handles the hard graphics work.

[herme3]

Ok, but doesn't the monitor still have to process that information into a picture? Wouldn't it work better to have the graphics card in the monitor, instead of the computer?

[Cap'n Refsmmat]

No, because the graphics card sends the information essentially as "pixel x,y color=384" format, and the monitor doesn't need to do any processing at all. The monitor just routes the input to the electron gun (or whatever type of display it has) and displays it.

[herme3]

Ok, thank you for the explanation.