Dell UltraScan P990 User Manual page 25

Table 3-6. Troubleshooting Problems (continued)
Symptom
Picture is scrambled
Color is not uniform
You cannot adjust
the monitor with the
buttons on the front
panel
Screen image is not
centered or sized
properly
Edges of the image
are curved
White lines show red
or blue shadows at
edges
Check these items
•
Check your video board manual for the proper monitor
setting.
•
Check this manual and make sure the monitor supports
the graphics mode and the frequency at which you are
trying to operate. Even if the frequency is within the
proper range, some video boards may have a sync pulse
that is too narrow for the monitor to sync correctly.
•
Degauss the monitor (page 1-9).
If you place equipment which generates a magnetic
field, such as a loudspeaker, near the monitor, or you
change the direction of the monitor, the color may not
be uniform.
The degauss function demagnetizes the metal frame of
the CRT to obtain a neutral field for uniform color repro-
duction. If a second degauss cycle is needed, allow a
minimum interval of 20 minutes for the best result.
•
If the Control Lock function is set to "ON," set it to
"OFF" using the OPTION OSD (page 1-9).
•
Adjust the size (page 1-7) or centering (page 1-7).
•
Some video modes do not fill the screen to the edges.
This problem tends to occur with certain video boards.
•
Adjust the geometry (page 1-7).
•
Adjust the convergence using the CONVERGENCE OSD
(page 1-9).
Troubleshooting 1-17