CompTIA A_ Certification All-In-One Exam Guide, Seventh Edition - Michael Meyers [338]
DirectX is not only for video; it also supports sound, network connections, input devices, and other parts of your PC. Each of these subsets of DirectX has a name, such as DirectDraw, Direct3D, or DirectSound.
DirectDraw Supports direct access to the hardware for 2-D graphics.
Direct3D Supports direct access to the hardware for 3-D graphics—the most important part of DirectX.
DirectInput Supports direct access to the hardware for joysticks and other game controllers.
DirectSound Supports direct access to the hardware for waveforms.
DirectMusic Supports direct access to the hardware for MIDI devices.
DirectPlay Supports direct access to network devices for multiplayer games.
DirectShow Supports direct access to video and presentation devices.
Microsoft constantly adds to and tweaks this list. As almost all games need DirectX and all video cards have drivers to support DirectX, you need to verify that DirectX is installed and working properly on your system. To do this, use the DirectX Diagnostic Tool. In Windows 2000/XP, you can find it in the System Information program. After you open System Information (it usually lives in the Accessories | System Tools area of the Start menu), click the Tools menu and select DirectX Diagnostic Tool (see Figure 19-73).
For Windows Vista/7, go to Start and type dxdiag in the Start search box. Press ENTER to run the program.
The System tab gives the version of DirectX. The system pictured in Figure 19-73 runs DirectX 10. You may then test the separate DirectX functions by running through the other tabs and running the tests.
So, what does DirectX do for video cards? Back in the bad old days before DirectX became popular with the game makers, many GPU makers created their own chip-specific APIs. 3dfx had Glide, for example, and S3 had ViRGE. This made buying 3-D games a mess. There would often be multiple versions of the same game for each card. Even worse, many games never used 3-D acceleration because it was just too much work to support all of the different cards.
That all changed when Microsoft beefed up DirectX and got more GPU makers to support it. That in turn enabled the game companies to write games by using DirectX and have them run on any card out there. The bottom line: When Microsoft comes out with a new version of DirectX, all of the GPU companies hurry to support it or they will be left behind.
Figure 19-73 The DirectX Diagnostic Tool
Trying to decide what video card to buy gives me the shakes—too many options! One good way to narrow down your buying decision is to see what GPU is hot at the moment. I make a point to check out these Web sites whenever I’m getting ready to buy, so I can see what everyone says is the best.
www.hardocp.com
www.tomshardware.com
www.sharkyextreme.com
Troubleshooting Video
People tend to notice when their monitors stop showing the Windows desktop, making video problems a big issue for technicians. Users might temporarily ignore a bad sound card or other device, but will holler like crazy when the screen doesn’t look the way they expect. To fix video problems quickly, the best place to start is to divide your video problems into two groups: video cards/drivers and monitors.
Troubleshooting Video Cards/Drivers
Video cards rarely go bad, so the vast majority of video card/driver problems are bad or incompatible drivers or incorrect settings. Always make sure you have the correct driver installed. If you’re using an incompatible driver, Windows defaults to good old 640 × 480, 16-color VGA. A driver that is suddenly corrupted usually doesn’t show the problem until the next reboot. If you reboot a system with a corrupted driver, Windows will do one of the following: go into VGA mode, blank the monitor, lock up, or