HP dc7900 - Convertible Minitower PC Service & Reference Manual page 266

Table D-6 Solving Display Problems (continued)
"Out of Range" displays on screen.
Cause
Video resolution and refresh rate are set higher than what the
monitor supports.
Vibrating or rattling noise coming from inside a CRT monitor when powered on.
Cause
Monitor degaussing coil has been activated.
Clicking noise coming from inside a CRT monitor.
Cause
Electronic relays have been activated inside the monitor.
High pitched noise coming from inside a flat panel monitor.
Cause
Brightness and/or contrast settings are too high.
Fuzzy focus; streaking, ghosting, or shadowing effects; horizontal scrolling lines; faint vertical bars; or unable to
center the picture on the screen (flat panel monitors using an analog VGA input connection only).
Cause
Flat panel monitor's internal digital conversion circuits may be
unable to correctly interpret the output synchronization of the
graphics card.
Graphics card is not seated properly or is bad.
Certain typed symbols do not appear correct.
Cause
The font you are using does not support that particular symbol. Use the Character Map to locate and select the appropriate
254 Appendix D Troubleshooting Without Diagnostics
Solution
Restart the computer and enter Safe Mode. Change the
settings to a supported setting then restart the computer so that
the new settings take effect.
Solution
None. It is normal for the degaussing coil to be activated when
the monitor is powered on.
Solution
None. It is normal for some monitors to make a clicking noise
when turned on and off, when going in and out of standby
mode, and when changing resolutions.
Solution
Lower brightness and/or contrast settings.
Solution
1. Select the monitor's Auto-Adjustment option in the
monitor's on-screen display menu.
2. Manually synchronize the Clock and Clock Phase on-
screen display functions. To download a SoftPaq that will
assist you with the synchronization, go to the following
Web site, select the appropriate monitor, and download
either SP32347 or SP32202:
1. Reseat the graphics card.
2. Replace the graphics card.
Solution
symbol. Click Start > All Programs > Accessories > System
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