Monitor Troubleshooting Guide
Complete solutions for common monitor problems. Fix flickering, no signal, dead pixels, color issues, ghosting, and more.
TestBeforeYouBuy Team
Updated December 14, 2025
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Quick Diagnosis
Select your symptom for targeted solutions:
No Signal / Black Screen
One of the most common and frustrating monitor issues. The monitor powers on but shows "No Signal" or remains black.
Troubleshooting Steps (In Order)
Check Cable Connections
Unplug and firmly reconnect both ends of your display cable. Check for bent pins on VGA/DVI connectors.
Try a Different Cable
Cables can fail. Test with a known-working cable. HDMI and DisplayPort cables are most prone to issues.
Try a Different Port
Use a different video output on your GPU. If using DisplayPort, try HDMI or vice versa.
Select Correct Input
Use the monitor's input button or OSD menu to manually select the correct input source.
Check GPU Seating
Power off, open your PC, and reseat the graphics card. Ensure power cables to the GPU are connected.
Test with Different Device
Connect a laptop, game console, or another PC to isolate whether the issue is the monitor or computer.
DisplayPort Specific Fix
If using DisplayPort and getting no signal, try this: In your monitor's OSD menu, look for "DisplayPort 1.2" or "DP Version" and toggle it. Some monitors default to DP 1.2 which may not work with older graphics cards.
Screen Flickering
Flickering can range from barely noticeable to constant blinking. Different causes require different solutions.
Constant Flickering
Screen flickers continuously regardless of content
- Fix: Check refresh rate matches monitor spec
- Fix: Try a different cable
- Fix: Update graphics drivers
- Fix: Disable G-Sync/FreeSync temporarily
Flicker at Low Brightness
Flickering only visible at low brightness settings
- Cause: PWM backlight dimming
- Fix: Increase brightness above 50%
- Fix: Use DC dimming if available in OSD
- Note: Some panels are more prone to this
Flicker with Adaptive Sync
Flickering when G-Sync/FreeSync is active
- Cause: Frame rate outside VRR range
- Fix: Enable VSync + G-Sync/FreeSync
- Fix: Cap frame rate below max refresh
- Fix: Use RTSS frame limiter
Random/Intermittent Flicker
Occasional flicker or brief blackouts
- Cause: Cable handshake issues
- Fix: Replace cable (especially long ones)
- Fix: Check for EMI interference
- Fix: Try different refresh rate
Dead and Stuck Pixels
Pixel defects are tiny dots that don't display correctly. Understanding the difference between stuck and dead pixels is key to fixing them.
Pixel Types and Fixes
Stuck Pixel (Red, Green, or Blue)
A subpixel that's stuck "on" - displays a constant color
Fixable? Often yes! Try these methods:
- 1. Use our Pixel Fixer Tool for 10-30 minutes
- 2. Gently massage the area with a soft cloth while running the fixer
- 3. Leave the pixel fixer running overnight
Dead Pixel (Black)
A pixel that doesn't light up at all - appears black
Fixable? Usually not. Dead pixels are typically permanent.
- 1. You can try the pixel fixer, but success rate is low (~5%)
- 2. Check warranty - most manufacturers have pixel policies
- 3. If new, return for exchange within return window
Hot Pixel (White)
A pixel stuck permanently on - appears white
Fixable? Sometimes. Similar to stuck pixels.
- 1. Try pixel fixer tool with rapid color cycling
- 2. Apply gentle pressure with a soft cloth
- 3. Contact manufacturer if under warranty
Color Problems
Color issues range from slight tints to completely wrong colors. Most can be fixed through software settings.
Colors Look Too Warm/Yellow
Common causes:
- - Night mode/blue light filter enabled
- - Color temperature set too low
- - sRGB mode not enabled
- - Windows Night Light active
Solutions:
- - Check Windows Display Settings for Night Light
- - Set color temperature to 6500K in monitor OSD
- - Enable sRGB mode for accurate colors
- - Check graphics driver color settings
Colors Look Too Cool/Blue
Common causes:
- - Color temperature set too high
- - "Cool" preset selected in OSD
- - Uncalibrated monitor
Solutions:
- - Lower color temperature to 6500K
- - Select "Standard" or "sRGB" preset
- - Calibrate with Windows Display Calibration
Washed Out/Dull Colors
Common causes:
- - Limited RGB range instead of Full
- - Low saturation/vibrance settings
- - Wrong color profile
- - HDR enabled on SDR monitor
Solutions:
- - NVIDIA: Change Output Dynamic Range to Full
- - AMD: Set Pixel Format to RGB 4:4:4 Full
- - Check monitor is set to "Full Range" in OSD
- - Disable Windows HDR if monitor doesn't support it
Color Banding/Gradients Not Smooth
Common causes:
- - 6-bit panel being dithered
- - Chroma subsampling (4:2:2 or 4:2:0)
- - Compressed video content
- - 8-bit color depth at high refresh
Solutions:
- - Enable 10-bit color if supported (NVIDIA Control Panel)
- - Use DisplayPort for higher bandwidth
- - Lower refresh rate to enable full color depth
- - Check panel specs - some are inherently 6-bit
Ghosting and Smearing
Ghosting appears as a trail behind moving objects. It's caused by slow pixel response times and is more noticeable in fast-paced content.
Ghosting vs Inverse Ghosting
Ghosting (Dark Trail)
A dark shadow trails behind moving objects
Cause: Slow pixel transition (undershoot)
Fix: Increase overdrive setting in monitor OSD. Try "Normal" or "Fast" mode.
Inverse Ghosting (Bright Corona)
A bright halo/corona appears around moving objects
Cause: Too much overdrive (overshoot)
Fix: Decrease overdrive setting. Use "Normal" or "Off" if needed.
VA Panel Black Smearing
VA panels are notorious for "black smearing" - dark objects leaving pronounced trails in dark scenes. This is a hardware limitation of VA technology. Some things that help:
- - Use the highest overdrive setting that doesn't cause inverse ghosting
- - Increase monitor brightness slightly (reduces black level)
- - Enable "Black Equalizer" if available
- - Unfortunately, this can't be fully fixed on VA panels
Screen Tearing
Tearing appears as horizontal "cuts" where the top and bottom of the screen show different frames. It occurs when your GPU's frame output doesn't sync with your monitor's refresh rate.
Solutions for Screen Tearing
Best Fix: Enable Adaptive Sync
If your monitor supports G-Sync or FreeSync:
- 1. Enable G-Sync/FreeSync in your monitor's OSD menu
- 2. NVIDIA: Enable "G-Sync Compatible" in NVIDIA Control Panel
- 3. AMD: Enable FreeSync in AMD Radeon Settings
- 4. Enable VSync in-game or driver for smoothest experience
Alternative: Enable VSync
If you don't have adaptive sync:
- - Enable VSync in game settings or graphics driver
- - Adds input lag but eliminates tearing
- - Use "Fast Sync" (NVIDIA) or "Enhanced Sync" (AMD) for reduced lag
Pro Tip: Frame Rate Limiting
For adaptive sync with VSync enabled, cap your frame rate 3-4 FPS below your monitor's max refresh rate. This keeps you within the VRR range and provides the smoothest experience.
Example: 144Hz monitor = cap at 140-141 FPS using RTSS or in-game limiter
Backlight Bleed and IPS Glow
Light leaking around the edges or corners of your screen, especially visible on dark scenes.
Backlight Bleed
Light leaking from edges/corners of the panel
- Location: Usually edges and corners
- Appearance: Bright spots regardless of viewing angle
- Cause: Manufacturing defect, poor frame fit
- Fixable? Sometimes loosening bezel screws slightly helps. Usually a return issue.
IPS Glow
Silvery glow from IPS panel corners
- Location: Corners, especially bottom corners
- Appearance: Changes with viewing angle
- Cause: Inherent to IPS technology
- Fixable? No - it's normal for IPS. Reduce brightness and view from direct angle.
Minimizing Light Bleed Impact
- Lower brightness: Reduces the visibility of backlight bleed significantly
- Don't watch in complete darkness: Some ambient light makes bleed less noticeable
- Increase viewing distance: Bleed is less visible from further away
- Use bias lighting: LED strips behind monitor reduce perceived bleed
Resolution and Scaling Issues
Problems with resolution, blurry text, or incorrect scaling can usually be fixed through settings.
Native Resolution Not Available
- Check: Graphics drivers are up to date
- Check: Cable supports required bandwidth (4K@60Hz needs HDMI 2.0 or DisplayPort 1.2+)
- Try: Create custom resolution in GPU control panel
- Try: Different cable or port
Blurry Text on High-DPI Monitor
- Fix: Set Windows scaling to 150% or 200% (Settings > Display > Scale)
- Fix: For specific apps: Right-click > Properties > Compatibility > High DPI settings
- Fix: Enable ClearType (search "ClearType" in Windows)
Image Not Filling Screen
- Check: Monitor scaling set to "Full" not "Aspect" or "1:1"
- Check: GPU scaling settings (NVIDIA/AMD control panel)
- Check: Running at non-native resolution
When to Return or RMA
Return Your Monitor If:
- Multiple dead pixels in center of screen
- Severe backlight bleed (light flooding dark scenes)
- Dead pixels appearing during warranty period
- Horizontal or vertical lines across display
- Flickering that persists after all troubleshooting
- Color uniformity issues (yellowing on one side)
- Physical damage from shipping
- Monitor won't power on after testing power cable
Document Before Returning
- 1. Take photos/video of the issue (dead pixels, backlight bleed, flickering)
- 2. Note the conditions (brightness level, what content shows the issue)
- 3. Document troubleshooting steps you've tried
- 4. Check manufacturer's pixel policy (most allow 3-5 dead pixels)
- 5. Keep all original packaging for returns
Diagnostic Tools
Frequently Asked Questions
Why is my monitor flickering?
Monitor flickering can be caused by incorrect refresh rate settings, faulty cables, outdated graphics drivers, PWM backlight dimming at low brightness, or interference from other devices. Start by checking your refresh rate settings match your monitor's specifications, then try a different cable.
How do I fix monitor no signal?
Check that cables are securely connected, try a different port or cable, ensure GPU is properly seated, update graphics drivers, and try connecting to a different device. If using DisplayPort, try enabling or disabling DisplayPort 1.2 mode in your monitor's OSD menu.
Can dead pixels be fixed?
Stuck pixels (colored) can sometimes be fixed using pixel fixing tools that rapidly cycle colors. True dead pixels (black) usually cannot be fixed. Try applying gentle pressure with a soft cloth while running a pixel fix tool. If the monitor is under warranty, contact the manufacturer.
Why does my monitor have ghosting?
Ghosting is caused by slow pixel response times, which is a panel characteristic. You can reduce ghosting by adjusting your monitor's overdrive/response time setting. Too much overdrive causes inverse ghosting (coronas). VA panels are more prone to ghosting in dark scenes.
How do I fix screen tearing?
Enable VSync in your game or graphics driver settings, or use adaptive sync technology (G-Sync/FreeSync) if your monitor supports it. Ensure your graphics drivers are up to date and that adaptive sync is enabled in both the monitor OSD and your graphics control panel.