27" 5K iMac Late 2015 - Long Boot, Scrambled Display?

[JWarrenJackson]

Hey everyone! My iMac's performance dropped drastically in the last 2 days and after another reboot, I get this mostly black screen with some odd colors. I've done some reading and for what I can surmise is that's it's a GPU and/or logic board issue?

Any ideas?

Thanks for any info in advance!

-Jim

 

[DeltaMac]

That's probably correct - GPU and/or logic board.
You can try reseating the RAM, which is doubtful to fix that issue, but is the easiest thing you can try.

If there is a possibility that you purchased AppleCare for your iMac, this will be the time to use that...

 

[mikehalloran]

I've done some reading and for what I can surmise is that's it's a GPU and/or logic board issue?

Uh yea....

Replace the NV RAM battery.

See if there's still a problem.

Reset the NV RAM. If anything changes, replace the battery.

Can it be GPU related? Maybe but you described the symptoms of a weak battery.

 

[JWarrenJackson]

Uh yea....

Replace the NV RAM battery.

See if there's still a problem.

Reset the NV RAM. If anything changes, replace the battery.

Can it be GPU related? Maybe but you described the symptoms of a weak battery.

I'll give that a shot!

Thank you!

 

[smirk]

@JWarrenJackson Any update on your computer? I'm curious if replacing the battery fixed your issues.

 

[JWarrenJackson]

@JWarrenJackson Any update on your computer? I'm curious if replacing the battery fixed your issues.

Problem solved! Dead fusion boot drive. Swapped it out and restored with a backup. I'm back in business.