CompTIA A+ 220-1201 (5.3 - Troubleshooting Display Issues)

Incorrect input source

• Is it connected?

- We wouldn't ask if it wasn't a real solution

- Check both power and signal cable

• Input selection on monitor

- HDMI, DVI, VGA, etc.

• Image is dim

- Check brightness controls

• Swap the monitor

- Try the monitor on another computer

• No video after Windows loads

- Use VGA mode (F8)

LCD projector bulbs

• LCD projectors and heat

- Very bright metal-halide bulbs

- Operate at around 1,000 degrees Celsius

• Cooling is always an issue

- Fans constantly cool the bulb

- Shuts down if temperatures are high

- Fan cools bulb slowly after light is off

• Replace a burnt-out bulb

- And clean dust from the air filters and external air input/output

Fuzzy image

• An LCD display is fixed

- The number of pixels doesn't change

• A display looks best when the video settings match a display's native resolution

- A mismatch can cause distortion

• If changing the display resolution,try using a multiple of the native resolution

- 2560 x 1600 is the same ratio as 1920 x 1200

Burn-in

A problem across all monitor types

- Some displays will pixel-shift

- You probably won't notice it

• LCDs have "image sticking"

- Try to remove by displaying a white screen for an extended period

Dead pixels

• Always black

- A manufacturing defect

• This probably isn't a problem on your side

- Not a cable or power issue

• Clean the monitor screen

- Damp cloth

• You'll have to replace the monitor

- No other option

Flashing screen

• Check the video cable connections

- A loose cable will cause loss of signal

• Replace the video cable

- Usually a quick fix

• The problem could be with the monitor

- Try switching the display

• Confirm the display settings in the operating system

- May not match the monitor

Incorrect color display

• Colors may not be properly represented

- Too much red, green, blue, yellow, etc.

• Monitor settings

- Tint

- Custom color presets

- Factory Reset

• Driver configuration

- Color tint

• OS configuration - Very blue

- Night light settings

Audio issues

• Many monitors include speakers

- No sound, low volume

• Monitor may have audio controls

- Check volume levels and mute status

• Confirm audio input over HDMI, DisplayPort, or Thunderbolt

- Check the HDMI audio output in the OS

• The monitor may support other audio input interfaces

- Check for audio jacks

Dim image

• Monitor video settings

- Brightness

- Contrast

• Check the OS

- Auto-dimming

- Dim on battery power

- Driver settings

• Backlight failure

- Some or all of the light

- May only be a section of the screen

Image quality problems

• Flickering, color patterns incorrect

- You can almost work with this

• Check the cable pins

- Especially if missing a color

• Distorted image and geometry

- Check the OS refresh rate and resolution settings

- Need to match the display specifications

- Check or replace cable

• Disable hardware acceleration

- Troubleshoot with the software drivers

Sizing issues

• The video output

- The display may scale to fit the image (or not)

- Check the display for a scaling option

Distorted image

• Lines, flashing colors, blocks

- Lines, flashing colors, blocks

- Difficult to see

• Hardware failure

- LCD panels are very easy to break

- No easy fix - replace the display

• Other hardware

- Bad cable

- Bad video adapter

• Software configuration

- Bad video driver