Selecting a Video Adapter

repair — Wed, 17 Feb 2010 01:29:57 +0000

High-quality video is necessary for any graphics-intensive activities such as Web surfing, high-graphics games, video and photographic editing, and others. High-quality video has two main components: general quality of the video adapter and monitor including the chipset, and amount and type of video memory. To understand the importance of sufficient video memory, it is necessary to understand how the amount of video memory affects the screen resolution and color depth (the total number of different colors a video adapter can output to the monitor). The easiest way to show this is through Tutorial 8.1.

Tutorial 8.1: Setting Display Properties in Windows (all versions)

Access Display Properties in one of two ways:

Double-click Display in Control Panel (see “System Configuration and Computer Hygiene,” for information on Control Panel).
Right-click any spot on the desktop with no icons and select either Properties or Active Desktop > Customize my desktop from the menu that appears.

On the Display Properties page, click the Settings tab. A page such as the one shown in Figure 8.2 appears.

Figure 8.2: Display Properties.

Click the down arrow next to the Colors box. You should see a choice of color depth. Table 8.1 lists the possible choices.

Table 8.1: Display Colors
Color Depth	Number of Colors	Useful for
16 Colors	16	Text and very simple graphics
256 Colors	256	Text and simple graphics
Medium (16 bit)	65,535	Text and most general graphics use, plus video editing and most photography editing
True Color (24 bit) or High Color (24 bit)	16,777,216	Text and any but the most demanding graphics use
Highest (32 bit) or True Color (32 bit)	4,294,967,295	Text and the most demanding graphics use

It is most doubtful that you will see all of these choices. Old video adapters don’t support the higher color levels, and newer ones might not show the lower or even support some of the intermediate levels.

Move the slider in the area labeled “Screen area,” “Screen resolution,” or equivalent. You’ll see that as the numbers change, the image in the sample screen on the page changes in size correspondingly.

Click OK or Apply. Regardless of whether you have changed color depth or resolution, in most or all cases, you’ll be shown the new screen and will be prompted to accept or reject the change. In some cases, the results will be unsatisfactory and you’ll have to change back. Other things that could happen include lowering of one parameter as you raise the other, or having few or no choices at all. These conditions could be caused by several factors, as listed in Table 8.2.

Table 8.2: Display Setting Anomalies
Anomaly	Possible Causes
No choices in either resolution or color depth, or both.	Certain LCD screens can display video at only one preset resolution. Design limitation of the video adapter or monitor. The computer is in Safe Mode. There is a problem with the adapter or its driver.
One parameter decreases as the other one is increased.	Lack of sufficient video memory to support high resolutions and large color palettes simultaneously.
The image is odd-shaped.	The aspect ratio of the selected screen resolution does not match that of the screen (4×3 for computer monitors).
The page displays unusable or poor quality video.	The settings exceed the capability of the video adapter or monitor.

By : Book-PC Repair and Maintenance: A Practical Guide

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Selecting a Video Adapter