PC Hardware in a Nutshell, 3rd Edition

2D Versus 3D

The first graphics accelerators were 2D models, designed to provide hardware acceleration for common display tasks (drawing and moving windows, scaling fonts, and so on) when running standard business applications under Windows. 2D accelerators essentially treat your display as a flat, two-dimensional workspace. Although one window may overlay another window, the top or foreground window always has focus.

Conversely, 3D accelerators treat your display as though it has depth. For example, when you play a 3D computer game, an onscreen character may walk in front of a table. The video adapter must determine the relative positions of the character and the table as seen from the viewer’s position and display that portion of the character that is in front of the table rather than the portion of the table that should be concealed by the character. 3D video cards also support a variety of supplemental functions to enhance realism—for example, adding textures to the surface of concrete or adding reflections to a pool of standing water. Adding these minor but visually important enhancements consumes a great deal of memory and processor power, so high-performance 3D video adapters are relatively expensive devices, with typical street prices of $125 to $300 or more.

Tip

Midrange 3D video adapters, those that are 12 to 18 months behind the current generation, sell for $50 or so, and provide all the 3D performance most people need. For example, Robert built a replacement for his primary ...