Is the screen flickering on bootup normal?

[MacAttackKev]

I've noticed that whenever I boot up my new pro (from shut down), after entering my password, as it loads, my screen would flicker on and off before entering the desktop. But otherwise, everything seems to be working fine after.

Just wondering if I should be concerned about that or is that normal?

 

[kentzh]

A few days ago, my friend and I were discussing this problem, and he found a solution. You try to set-Security and Privacy-File Vault, turn off Enable File Vault. You will find that this problem has been resolved.

 

[sionell]

A few days ago, my friend and I were discussing this problem, and he found a solution. You try to set-Security and Privacy-File Vault, turn off Enable File Vault. You will find that this problem has been resolved.

I wouldn't recommend turning off File Vault. It makes the data on your drive secure. How does turning off File Vault solve a flickering-screen-on-bootup problem?

 

[sevoneone]

It's normal. My new 14" MBP does this, My 2018 15" MBP with FileVault enabled also did it. The FileVault UI is a pre-boot environment that hands off to macOS, the flickering you see is that handoff. It is expected behavior and not worth sacrificing the security of having FileVault turned on.

 

[MacAttackKev]

Hmm is this something you would notice on a newer OS?
I still have my older air running Mojave and I do have FileVault enabled, but I don't have that flickering situation on it just my pro?

 

[funkbass101]

I've noticed that whenever I boot up my new pro (from shut down), after entering my password, as it loads, my screen would flicker on and off before entering the desktop. But otherwise, everything seems to be working fine after.

Just wondering if I should be concerned about that or is that normal?

I seem to have the same problem. I just opened a brand new MacBook Pro 16 M1 Max and right out of the box I had noticed a screen flicker. It persists after boot up as well. I updated to the latest macOS and did the SMC and NVRAM reset as well. Now the problem still persists on and off... I did not expect that on a top of the line computer right out of the box..

 

[roman.stapunov]

What “flickering” exactly does mean? Since I enabled FileVault on my Mac mini two years ago and MacBook Pro later I always see “my screen would switch on and off 1-2 times before entering the desktop after entering login and password” If this is what is under discussion here then I am afraid this expected behaviour

 

[funkbass101]

No... More like flashes / parts of the screen going black...

 

[gren81]

FWIW: I had flickering during boot-up on my Mid-2012 MBP (Intel) for months until this morning.It is now fixed and not a hardware issue for me.

My flickering on boot-up was the login / boot screen would flash white->gray->white->gray->… in rapid succession.

Apple Support helped me this morning to resolve it. Running Disk Utility OS Recovery did not identify any issues. Then , I focused on NVRAM which stores display and other start up data.

From Apple Advisor:

“Hello! Please follow this to reset the NVRAM: Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P, and R. You can release the keys after about 20 seconds, during which your Mac might appear to restart. If issue persist please contact us back with your follow up number: [….]”

I then ran the NVRAM for (Intel only) which fixed it. Apple’s documentation indicates that the Apple M1 and M1 Pro do not have NVRAM.

I am not sure what one does for M1 and M1 Pro. You can search on NVRAM as the documentation does speak to alternatives.

 

[funkbass101]

Thanks guys, so far no luck!!! However I do noticed reduced flicker when connected to a power source and much more when running on battery.
When on power source, if connected to an external monitor then the MacBook frequently crashes! It crashes and reboots with this "SOCD report detected: (AP watchdog expired)"