If your MacBook screen starts flickering, flashing black, showing green lines, or briefly going blank suddenly or after an update, don't panic.
In most cases, this is caused by a software conflict after a macOS update, GPU switching behavior, or an external display issue - not a dead screen.
Follow this guide, and you'll:
- Identify what kind of flicker you're seeing
- Determine whether it's software or hardware
- Apply the right fix in the right order
- Know when it's time to contact Apple
Identify the type of flickering on your Mac screen first
Before trying random fixes, narrow it down:
Case A: Flickers only after updating to macOS Sequoia
Likely cause: driver conflict or system bug.
Case B: Flickers only when using an external monitor
Likely cause: refresh rate mismatch or cable instability.
Case C: Flickers even at startup (before login screen)
Possible hardware issue.
Case D: Screen briefly flashes black when switching apps
Often due to GPU switching behavior.
Understanding your specific situation saves time.
Fix 1: Restart (Quick GPU reset)
If flickering started recently:
- Click > Restart.
- Wait 60 seconds after reboot.
Why this works: A restart reloads display drivers and clears temporary GPU glitches.
If the flicker disappears after a restart but returns later, the issue is likely software-related. Move on to the following solutions.
Fix 2: Disconnect the external display (Very common cause)
If you use a second monitor, the external display and the Mac may have mismatched refresh rates (e.g., 60Hz vs. 75Hz). This may cause screen flickering, especially when moving windows between the displays or interacting with both screens.
Also, the faulty or incompatible HDMI, DisplayPort, or Thunderbolt cable/adapter can lead to unstable connections and the Mac screen flickering.
Thus, you can:
- Unplug the HDMI / DisplayPort / Thunderbolt cable
- Test your MacBook screen alone
To check refresh rate:
System Settings > Displays > Select external display > Refresh Rate
Match both displays to 60Hz if possible.
If flickering stops after disconnecting, the Mac screen is fine; the issue is external.
Fix 3: Boot into Safe Mode (Software conflict test)
Safe Mode loads only essential system components. If the flickering issue disappears in Safe Mode, it shows that a third-party app or extension is causing it. In that case, restart your Mac normally and uninstall the recently installed apps one by one.
Here's how to enter Safe Mode on Mac:
On Apple Silicon (M1/M2/M3):
- Shut down completely.
- Hold the power button until the startup options appear.
- Select your disk.
- Hold Shift > Click "Continue" in Safe Mode.
On Intel Macs:
- Restart.
- Hold Shift immediately.
When you see the words "Safe Boot" appearing on the menu bar (top right of your screen), it means you are entering Safe Mode successfully.
Fix 4: Disable Automatic Graphics Switching (Intel MacBook Pro Only)
Intel-based MacBook Pros have dual GPUs. Sometimes the switch between integrated and dedicated graphics causes flickering.
So, try disabling automatic graphics switching:
- System Settings > Battery > Options.
- Turn off "Automatic graphics switching."
Note:
1. This may reduce battery life because the Mac will use dedicated graphics continuously.
2. This setting does not exist on Apple Silicon Macs.
Fix 5: Disable True Tone (Quick test)
True Tone is a new technology on Mac devices from 2018 and later. It requires a constant GPU to help it adjust the color of the screen display to fit the changing environment.
If any error occurs during this process, your screen may flicker. So, you can try to turn off True Tone.
- Open System Preferences and click Displays.
- Uncheck True Tone on the window.
Fix 6: Switch to regular image wallpaper (If you use a dynamic wallpaper)
Some users discussed in the Apple community say that the MacBook screen flickering after the macOS Sequoia update resulted from the dynamic wallpaper.
And custom wallpaper is verified not the culprit. If you use the dynamic wallpaper, you can try to change to the regular one and see if the issue continues. If it is, jump to the next solution.
Fix 7: Reset NVRAM / PRAM (Intel Macs only)
NVRAM is short for nonvolatile random-access memory. It stores some settings and system-related information, such as recent kernel panic information, start-up selection, display resolution, etc.
So, when the MacBook Pro screen flashes, resetting NVRAM / PRAM may work.
- Shut down your MacBook Pro.
- Reboot your computer and simultaneously press down the Option + Command + P + R key combination.
- Release the keys until you hear the second startup sound. (If you have a T2-equipped MacBook, release the keys when seeing the Apple logo appear and disappear twice.)
Note: Apple Silicon Macs reset NVRAM automatically during startup; a manual reset is not required.
Fix 8: Update macOS
Sometimes, flickering is caused by early system bugs in macOS Thaoe, Sequoia, or other versions.
Check:
System Settings > General > Software Update
Install any available patch updates.
Before updating, back up using Time Machine. This is to avoid data loss triggered by the update.
How to tell if it's hardware damage
Software flickering usually:
- Stops in Safe Mode
- Appears after updates
- Does NOT show in screenshots
Hardware flickering often:
- Appears before the login screen
- Shows vertical permanent lines
- Happens even in Recovery Mode
- Shows on the internal screen while the external display works perfectly
Quick test:
Take a screenshot during flickering. If the screenshot looks normal on another device, the GPU output is fine; the issue is likely the display panel.
If flickering appears in the screenshot itself, it may be GPU-related.
If the problem happens before macOS loads, contact Apple Support.
Why is your MacBook screen flickering?
The main reasons are the incompatibilities or errors between the operating system and the Graphics Processing Unit (GPU). Besides, diverse reasons can make the MacBook screen flicker.
Here we've summarized the common reasons why your MacBook Pro/Air screen is flickering with horizontal lines or in full-screen.
- Interference from the external display
- Energy saver glitches
- Integrated graphics process issues
- Hardware damage to your MacBook
- macOS Sequoia bugs
- Third-party software conflicts
- Insufficient disk space on your Mac
Final Thoughts
Most MacBook screen flickering issues are caused by:
- External display conflicts
- GPU switching behavior
- Post-update software glitches
Start with simple isolation testing before assuming hardware failure.
If the issue disappears in Safe Mode or after disconnecting your monitor, your Mac is likely healthy.
If it flickers before macOS even loads, it's time for professional repair.
If your MacBook screen can't stop flickering and eventually won't start up, in this case, you can try iBoysoft Mac Recovery Mode to rescue your files ASAP before they are permanently lost.
This special mode loads iBoysoft Data Recovery for Mac directly from iBoysoft's server and can scan your Mac to help you get files off the Mac to a connected external drive.
FAQs about MacBook Pro screen flickering
- QWhy does my MacBook screen flicker?
-
A
This problem is usually caused by software incompatibilities, and errors between the macOS and Graphics Processing Unit (GPU).
- QShould I recover data before fixing the MacBook Pro flickering issue?
-
A
Yes. As some of the ways to fix the flickering screen may cause data loss, you'd better back up data on your Mac before fixing the issue. If your MacBook Pro screen is not only flashing but also freezing, you can recover data in macOS Recovery mode with iBoysoft Data Recovery for Mac. This Mac data recovery software helps recover data from a Mac that even won't boot.
- QWhy is the MacBook screen flickering problem still unresolved after I have tried every solution?
-
A
The flickering screen issue may not only be caused by software problems. It can also result from screen resolution damage. You can go to a repair center to change a display.