Symptom Possible Cause Items to Check Typical Solution. Color pat- Incorrect color Check the color man- terns incor- management agement settings for the rect profile

Color pat-	Incorrect color	Check the color man-
terns incor-	management	agement settings for the
rect	profile	display.

Rerun the Color Management Wizard in Windows or use a third-party color management tool such as DataColor’s Spyder or Pantone’s Huey.

Dim image	Incorrect bright-	Check the brightness,
	ness or contrast	contrast, and gamma
	settings	settings for the display.

If installed, use the screen management settings for NVIDIA or AMD video cards or use the Windows Color Management Wizard.

	LCD display:	Shine a flashlight on the	Test inverter; if damaged,
	Failure of inverter	display; if the desktop	replace.
		is visible, check the
		inverter.

	LCD display:	Check the inverter first;	Replace the backlight or
	Failure of back-	if the inverter is okay,	the entire LCD panel if
	light	the backlight has failed.	cost-effective.

Flickering	CRT display:	Check the vertical	Set the vertical refresh
image	Vertical refresh	refresh rate setting in	rate to 75Hz or higher.
	rate too low	advanced display prop-	Adjust the screen height,
		erties.
		width, and centering after

			selecting the refresh rate
			as needed.

LCD display	“Flickering” on an LCD
on VGA port:	is actually pixel swim
Problems with	due to a poor analog/
analog/digital	digital conversion.
conversion	Use the Auto button on

	display to resynchronize
	display.

Use DVI, HDMI, or DisplayPort with the LCD display if available on the display and computer to have a pure digital con-nection.

Interlaced verti-	Check the refresh rate
cal refresh rate	selected.
selected	Interlaced resolutions

	require long-decay
	phosphors and are sel-
	dom used today except
	with 1080i HDTV.

Select the correct non-interlaced refresh rate (usually 60Hz for LCD, LED displays; 75Hz or higher recommended for CRTs).

Chapter 9: Troubleshooting 181

Symptom	Possible Cause	Items to Check	Typical Solution

Distorted	CRT display:	Use onscreen display	Different resolutions
image	Bowing out (bar-	(OCD) to correct distor-	and refresh rates require
	rel) or bowing	tion.	unique settings.
	in (pincushion)		Check with the user to
	distortion
		determine the preferred

			resolutions and refresh
			rates and adjust those
			first.

	CRT display:	Electromagnetic inter-	Look for interference
	Wavy lines	ference from nearby	sources such as micro-
		poorly shielded devices.	wave ovens and move
			them away from the
			display.
			Replace the CRT with an
			LCD or LED display.

	CRT or LCD dis-	The display may use	Change the resolution to
	play: Resolution	compression to display	the native setting (LCD,
	too high for dis-	the video signal.	LED).
	play		Change the resolution to

			maximum supported by
			flicker-free vertical reso-
			lution (CRT).

Discoloration	CRT: Magnetic	Use the degaussing	If not available in the
(degaussing)	distortion in	option in the onscreen	onscreen menu, look for
	shadow mask	menu.	degaussing button on
			display or turn off the
			display, wait a couple of
			minutes, and turn it on
			again.

BSOD	Various problems	Note the STOP error	Research the STOP error
(STOP Error)	with Windows	code.	code at http://support.
	configuration or		microsoft.com.
	hardware		Replace any defective or

			incompatible hardware or
			software.

182 CompTIA A+ Quick Reference