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Chapter 10—Video and Audio
Table 10.24 Troubleshooting Video Capture Devices Continued
Device Type Problem Solution
USB devices Device can’t be Use Windows 98 or above; late versions
detected or doesn’t of Windows 95 have USB drivers, but
work properly. they often don’t work; if you use a USB
hub, make sure it’s powered.
Interface cards Card can’t be detec- Check for IRQ conflicts in Windows
(all types) ted or doesn’t work. Device Manager; consider setting card
manually if possible.
All devices Capture or installation Use the newest drivers available; check
problems. manufacturer’s Web site for updates,
FAQs, and so on.
Testing a Monitor with Common Applications
Even without dedicated test and diagnostics software, you can use
the software accessories (WordPad, Paint, and so on) that come
with Microsoft Windows to test a monitor for picture quality.
One good series of tasks is as follows:
• Draw a perfect circle with a graphics program. If the displayed
result is an oval, not a circle, this monitor will not
serve you well with graphics or design software.
• Using a word processor, type some words in 8- or 10-point
type (1 point equals 1/72 inch). If the words are fuzzy or if
the black characters are fringed with color, select another
monitor.
• Turn the brightness up and down while examining the corner
of the screen’s image. If the image blooms or swells, it is
likely to lose focus at high brightness levels.
• Display a screen with as much white space as possible and
look for areas of color variance. This might indicate a problem
only with that individual unit or its location, but if you
see it on more than one monitor of the same make, it can be
indicative of a manufacturing problem; or it could indicate
problems with the signal coming from the graphics card.
Move the monitor to another system equipped with a different
graphics card model and retry this test to see for certain
whether it’s the monitor or video card.
• Load Microsoft Windows to check for uniform focus. Are the
corner icons as sharp as the rest of the screen? Are the lines
in the title bar curved or wavy? Monitors usually are sharply
focused at the center, but seriously blurred corners indicate a
poor design. Bowed lines can be the result of a poor video