Appendix B

Diagnostic Video Tests

The Video Test Group of the Dell Diagnostics consists of the following eight tests, each of which verifies a particular video function or group of functions on your built-in display or on an external monitor:

Video Memory Test — Checks the integrity of char- acters generated from data in the video memory

Video Hardware Test — Checks the functions of the cursor register and the horizontal and vertical retrace bit registers

Text Mode Character Test — Checks the video sub- system’s ability to present text mode data

Text Mode Color Test — Checks the video sub- system’s ability to present color in text modes

Text Mode Pages Test — Checks the video sub- system’s ability to map and present all available video text pages on the display or monitor, one page at a time

Graphics Mode Test — Checks the video sub- system’s ability to present graphics mode data and colors

Color Palettes Test — Checks the video subsystem’s ability to display all available colors

Solid Colors Test — Checks the video subsystem’s ability to show screens full of solid colors and to dis- play all pixels

All of these tests, except the Video Memory Test and the Video Hardware Test, are interactive. These interactive tests display images on the display or monitor and require you to respond with the following steps:

1.Examine a displayed image for correctness.

2.If an image is correct, type y.

3.If an image is incorrect, type n.

The following sections describe each of the tests in the Video Test Group.

Video Memory Test

The Video Memory Test verifies the integrity of the video memory on the system board. When a test is com- plete, a message indicates whether the video memory has passed or failed the test. This test does not require any interaction on your part.

Video Hardware Test

The Video Hardware Test verifies the operation of the cursor registers and the horizontal and vertical retrace bit registers. When a test is complete, a message indicates whether these registers have passed or failed the test. This test does not require any interaction on your part.

Text Mode Character Test

The Text Mode Character Test consists of a group of sub- tests that display printable characters and character attributes. The subtests check character quality and the ability of the display or monitor to show the characters correctly. A prompt at the bottom of each screen asks you to decide whether the display is satisfactory and to respond by typing y or n.

If you respond affirmatively to each subtest, the Text Mode Character Test passes. A negative response to any subtest causes the test to fail.

Diagnostic Video Tests

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Dell 3000 manual Diagnostic Video Tests, Video Memory Test, Video Hardware Test, Text Mode Character Test