There might be an image on the display unit, but it might exhibit unusual artifacts or glitches
might be due to a fault in the display itself or with the input source (the signal from the video card)
Common Issues
Dim image
Use the OSD to check the brightness and contrast controls to make sure they are not turned all the way down
possible that a power-saving mode is dimming the display
possible that an adaptive brightness, auto-brightness, or eye-saving feature of the device or operating system has been enabled
These reduce brightness and contrast and can use lower blue-light levels
This type of feature might activate automatically at a certain time of day or could use an ambient light sensor to trigger when the room is dark
If the image is almost invisible, the display’s backlight has probably failed
unit will have to be repaired under warranty or replaced
Fuzzy image
If the output resolution does not match the display device’s native resolution, the image will appear fuzzy
typically happens if the video card’s driver is faulty or incorrectly configured
E.g., the TFT monitor’s resolution might be 1920x1080, but the video card is set to 1024x768
Use the OS to change the output resolution or update the driver
Flashing screen
Check the video cable and connectors
If the connector is not securely inserted at both ends, this could cause flickering
A flickering or flashing image could also be caused by the display’s backlight or circuitry starting to fail
Other symptoms of a failing display include:
bright or dim bands or lines
bright spots at the edge of the screen
will typically require the display to be repaired under warranty or replaced
Dead pixels
Defects in a flat-panel monitor may cause individual pixels to be “stuck” or “dead”
If a digital display panel has stuck (constantly bright) pixels, and the panel cannot be replaced under warranty, there are software utilities available to cycle the pixel through a series of relatively extreme color states to try to reactivate it
Fixed pixels can also sometimes be reactivated by gently pressing or tapping the affected area of the screen with a stylus or pencil eraser
there is the risk of causing further damage or scratching the screen
Dead pixels (solid black) cannot usually be fixed
Burn-in
When the same static image is displayed for an extended period, the monitor’s picture elements can be damaged
a ghost image is “burned” permanently onto the display
Devices such as plasma screens and organic LED (OLED) displays can be more vulnerable to burn-in than ordinary TFT/LED displays
Always ensure that a display is set to turn off, or use an animated screen saver when no user input is detected
Incorrect color display
If a computer is used to produce digital art, it is very important that the display be calibrated to scanning devices and print output
Color calibration (or workflow) refers to a process of adjusting screen and scanner settings so that color input and output are balanced
Color settings should be configured with the assistance of a color profile
use the Color Management applet in Control Panel along with test card color patterns and spectrophotometers to define a color profile and verify that the display matches it
may also come across color glitches, such as purple or green horizontal lines or colors changing unexpectedly
usually caused by a faulty or loose connector or cabling that is either faulty or insufficient quality for the current image resolution
Try replacing the cable. If this does not fix the issue, there could be a hardware fault in either the monitor or graphics adapter
Audio issues
HDMI and DisplayPort can deliver a combined video and audio signal if that is supported by the video card
DVI and VGA cannot carry a sound signal, so the speakers must be connected to the computer’s audio ports using 3.5mm jacks
If there is no sound from built-in or separate speakers, check power, cables/connectors, and any physical volume control on the speaker device
If you can discount these issues, use the OS to verify that the audio output is set to the correct device and check the OS volume control