Dell Inspiron 7000 Reference And Troubleshooting Manual page 98

4-18 Dell Inspiron 7000 Reference and Troubleshooting Guide
Video test group also provides additional subtests to test the color features of the
color display or an external color monitor.
NOTE: The video subsystem of your computer's display may support video resolu-
tions that are not supported on an external monitor. When the video subtests are run
on an external monitor, some of the test screens may flicker and appear to malfunc-
tion. This condition does not affect the accuracy of the video subtests or indicate a
hardware problem.
Many of the symptoms that would prompt you to run a subtest in the Video test
group are obvious, because the display is the visual component of the computer.
Before you run the Video test group or any of its subtests, you should make sure that
the problem is not occurring in the software or caused by a hardware change.
If the following symptoms still occur, run the appropriate test(s) as follows:
If your display or external monitor shows a partially formed or distorted image,
run all of the subtests in the Video test group.
If the alignment of text or images is off, regardless of the program you are run-
ning, run the Text Mode Character Test, Text Mode Pages Test, and Graphics
Mode Test.
If the color on the display or external monitor is intermittent or not displayed at all,
run the Text Mode Color Test, Color Palettes Test, and Solid Colors Test.
If your display or external monitor malfunctions in one mode but works fine in
another (for example, text is displayed correctly, but graphics are not), run the
Text Mode Character Test, Text Mode Color Test, Text Mode Pages Test, and
Graphics Mode Test.
The eight subtests in the Video test group confirm the following video functions:
Video Memory Test
Checks the read/write capability of the video memory in various video modes.
Video Hardware Test
Checks the cursor registers and the horizontal and vertical retrace bit registers in
the video controller.
Text Mode Character Test
Checks the video subsystem's ability to present data in text modes.
Text Mode Color Test
Checks the video subsystem's ability to present color in text modes.