IBM 628791U - PC 300 GL, User Manual

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Monitor Problems
Monitor Problems Action
General monitor
problems. Some IBM monitors have their own self-tests. If you
suspect a problem with your monitor, see the
information supplied with the monitor for adjustment
and testing instructions.
If you cannot find the problem, check the other listings
on monitor problems in this table.
If the problem cannot be corrected, have the monitor
and computer serviced.
Wavy, unreadable,
rolling, distorted, or
jittery screen images. If the monitor self-tests show that the monitor is
working properly, verify that:
1. The location of the monitor is appropriate.
Magnetic fields around other devices, such as
transformers, appliances, fluorescent lights, and
other monitors might be causing the problem. To
determine if the location is causing the problem:
a. Turn off the monitor. (Moving a color monitor
while it is turned on might cause screen
discoloration.)
b. Adjust the placement of the monitor and other
devices so that they are at least 305 mm (12
in.) apart. Also, when relocating the monitor,
be sure it is at least 75 mm (3 in.) from the
diskette drives to prevent diskette drive
read/write errors.
c. Turn on the monitor.
2. An IBM monitor signal cable is properly connected
to the monitor and computer, and that the cable is
installed securely. Non-IBM monitor signal cables
might cause unpredictable problems.
3. You are not trying to run your monitor at a higher
refresh rate than the monitor supports. See the
documentation supplied with your monitor for
supported refresh rates.
Note: An enhanced monitor signal cable with
additional shielding might be available for your
monitor. See your IBM reseller or marketing
representative for information.
If the problem cannot be corrected, have the monitor
and computer serviced.
Chapter 8. Troubleshooting
109