Resolution
The two factors that impact the amount of video RAM needed on the video card are
resolution and color depth. Each pixel of the display requires a certain amount of data
to encode exactly how it should appear. As the number of pixels used to create the dis-
play goes up, so does the total amount of data used to describe the display. For exam-
ple, about 6MB of data are needed to generate a true color image for a display using
1600 × 1200 resolution.
Resolution is the number of pixels used to generate a display. While it’s true that the
size of the display (such as 15-inch, 17-inch, etc.) has some bearing on the number of pixels
available, using more pixels to create an image will obviously increase the amount of detail
in the picture and improve its quality. A monitor using 640 × 480 resolution (640 pixels on
each horizontal line and 480 rows of pixels) uses 307,200 pixels to create its display. If the
same monitor is set to a resolution of 1280 × 960, it uses 1,228,800 pixels, and in the same
display space. As the pixel count increases on any monitor, the size of each pixel and the
space around it must decrease in order to fit in the display space.
As the resolution increases, the detail in the display also increases, while its size
decreases,aswasillustrated earlier in Figures 12-1 and 12-2. Try using the Settings tab on
the Display Properties of a Windows PC to change the display resolution. Here’s how:- On the Windows Desktop, right-click an empty space to display the Desktop’s
shortcut menu, shown here: - Select Properties to open the Display Properties window, shown in Figure 12-3.
- Select the Settings tab (as shown in Figure 12-3) to display the resolution
and color depth settings currently in use. Make a note of the current display
settings in use. - Slide the pointer in the Screen Area setting to the left to select 640 × 480 and
choose 256 colors from the Colors pull-down list.
Chapter 12: Video Cards^261