IBM NetVista 6058, Hardware Maintenance Manual

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If the voltages are not correct, and the power cord is good, replace the power
supply.
Display
If the screen is rolling, replace the display assembly. If that does not correct
the problem, replace the video adapter (if installed) or replace the system
board.
If the screen is not rolling, use the following procedure to run the display
self-test.
1. Power-off the computer and display.
2. Disconnect the display signal cable.
3. Power-on the display.
4. Turn the brightness and contrast controls clockwise to their maximum
setting.
5. Check for the following conditions.
v
You should be able to vary the screen intensity by adjusting the contrast
and brightness controls.
v
The screen should be white or light gray, with a black margin (test
margin) on the screen.
Note: The location of the test margin varies with the type of display. The
test margin might be on the top, bottom, or one or both sides.
If you do not see any test margin on the screen, replace the display. If
there is a test margin on the screen, replace the video adapter (if installed)
or replace the system board.
Note:
During the first two or three seconds after the display is powered
on, the following might occur while the display synchronizes with
the computer.
v
Unusual patterns or characters
v
Static, crackling, or clicking sounds
v
A “power-on” hum on larger displays
A noticeable odor might occur on new displays or displays recently
removed from storage.
These sounds, display patterns, and odors are normal. Do not
replace any parts.
If you are unable to correct the problem, go to “Undetermined problems” on
page 171.
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Hardware Maintenance Manual: IBM NetVista Computer Types 6058, 6059, 6269, 6568, 6569, 6578, 6579, 6648,
6649