Hi folks,
J has a 2011 i7 27" iMac at work running 10.12.6. She's had good luck with it, but a couple of weeks ago it started acting weird. It would spontaneously reboot, or on startup in the morning it would go 50% on the progress bar and then change to a white screen. And then reboot.
No problem, I thought, we'll do some checks - it's probably just a bad spot on the 2TB Hitachi hard drive...
Hmm. The Recovery boot won't work and it won't boot from a USB. I can't boot from a DVD either.
Zap the PRAM. OK, we've got the "booommmm" bootup sound again.
Hold Option/Alt key, can see the boot drive and the recovery partition....
(Off and on attempts to get to Disk Utility via the Recovery boot over several days....)
What's this? Success!! Run Disk Utility - What? Nothing's wrong???
Run the Apple hardware tests. What? Nothing's wrong???
Oh well, I'll buy a copy of Disk Warrior over the weekend and have it fix things on Monday (yesterday).
Hey, I was able to get the Recovery boot to work again and was able to run Disk Warrior!! Yay, it found some things to fix, but they seem really minor (9 icons, and a slightly more serious bitmap issue). Replace the bad xxxx. Ok.
Yay!! It booted up!
Quick!! Run Time Machine and dump everything to a new external 2TB drive (only $70 at MicroCenter). Let it run overnight.
It was still running Ok this morning (backup finished at 11 PM), shut down, and reboot. Starts up fine. Success!!!
So, J puts it back on her desk, hooks up her USB hub and wireless Logitech mouse. Everything seems fine, for several hours, she's working on an e-mail and...
Blue screen.
On rebooting with only apple mouse and keyboard, white screen.
It won't boot now. None of the various partially-successful steps earlier work now.
Grrr....
In looking around for previous comments on these things, some people were saying it was a graphics card issue, and others were saying it was a firmware issue with the HD. Neither made much sense to me (there was never any sign of video corruption, and all the tests say the HD is Ok).
I did some more looking around and found this:
https://www.youtube.com/watch?v=zoOchEUPBkI
Of course!! I remember an old PC that would have all sorts of issues with rebooting, not booting, etc., because the CMOS battery had died. It's probably dying on the iMac as well - it is nearly 8 years old after all...
Of course, I'd have to take the screen off and the LCD display, but it shouldn't be a huge deal...
OMFG!
As that video illustrates, you basically have to disassemble the entire stupid thing to gain access to the battery!!!!11ONE (I was hoping that the video was of a different model.)
:-/
It's still possible it's the graphics card (I haven't verified that it actually is the battery) - but it has all the symptoms of the boot sequence being mangled because the PRAM settings aren't being saved. We really can't justify spending more time trying to diagnose it, but it's a real shame that an expensive computer like this will probably be surplussed because the $3 battery died....
A week ago (when it wouldn't boot) she was able to order a new 5k 27" i7 (the top one just below the iMac Pro), 32 GB RAM, 1 TB SSD. It would be great if it also lasts for 8 years!
HTH someone out there. Keep your eyes peeled, Ashton! ;-)
Cheers,
Scott.
J has a 2011 i7 27" iMac at work running 10.12.6. She's had good luck with it, but a couple of weeks ago it started acting weird. It would spontaneously reboot, or on startup in the morning it would go 50% on the progress bar and then change to a white screen. And then reboot.
No problem, I thought, we'll do some checks - it's probably just a bad spot on the 2TB Hitachi hard drive...
Hmm. The Recovery boot won't work and it won't boot from a USB. I can't boot from a DVD either.
Zap the PRAM. OK, we've got the "booommmm" bootup sound again.
Hold Option/Alt key, can see the boot drive and the recovery partition....
(Off and on attempts to get to Disk Utility via the Recovery boot over several days....)
What's this? Success!! Run Disk Utility - What? Nothing's wrong???
Run the Apple hardware tests. What? Nothing's wrong???
Oh well, I'll buy a copy of Disk Warrior over the weekend and have it fix things on Monday (yesterday).
Hey, I was able to get the Recovery boot to work again and was able to run Disk Warrior!! Yay, it found some things to fix, but they seem really minor (9 icons, and a slightly more serious bitmap issue). Replace the bad xxxx. Ok.
Yay!! It booted up!
Quick!! Run Time Machine and dump everything to a new external 2TB drive (only $70 at MicroCenter). Let it run overnight.
It was still running Ok this morning (backup finished at 11 PM), shut down, and reboot. Starts up fine. Success!!!
So, J puts it back on her desk, hooks up her USB hub and wireless Logitech mouse. Everything seems fine, for several hours, she's working on an e-mail and...
Blue screen.
On rebooting with only apple mouse and keyboard, white screen.
It won't boot now. None of the various partially-successful steps earlier work now.
Grrr....
In looking around for previous comments on these things, some people were saying it was a graphics card issue, and others were saying it was a firmware issue with the HD. Neither made much sense to me (there was never any sign of video corruption, and all the tests say the HD is Ok).
I did some more looking around and found this:
https://www.youtube.com/watch?v=zoOchEUPBkI
Of course!! I remember an old PC that would have all sorts of issues with rebooting, not booting, etc., because the CMOS battery had died. It's probably dying on the iMac as well - it is nearly 8 years old after all...
Of course, I'd have to take the screen off and the LCD display, but it shouldn't be a huge deal...
OMFG!
As that video illustrates, you basically have to disassemble the entire stupid thing to gain access to the battery!!!!11ONE (I was hoping that the video was of a different model.)
:-/
It's still possible it's the graphics card (I haven't verified that it actually is the battery) - but it has all the symptoms of the boot sequence being mangled because the PRAM settings aren't being saved. We really can't justify spending more time trying to diagnose it, but it's a real shame that an expensive computer like this will probably be surplussed because the $3 battery died....
A week ago (when it wouldn't boot) she was able to order a new 5k 27" i7 (the top one just below the iMac Pro), 32 GB RAM, 1 TB SSD. It would be great if it also lasts for 8 years!
HTH someone out there. Keep your eyes peeled, Ashton! ;-)
Cheers,
Scott.