Late 2012 21" beyond slow/cannot install macOS

tdubbed

macrumors newbie
Sep 9, 2019
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Hello, everyone. Apple is slowly devouring me, which makes figuring out this iMac vital to my happiness.

I have this late 2012 iMac that my work is getting rid of. The thing is slower than molasses. It can boot into the OS, but even simple tasks are unbearable. It has a Samsung 1TB, 5400RPM drive, and everything I've read online tells me that the hard drive is failing... but..

I can't even install macOS on a new SSD. Constantly hangs during install. Things I have tried:

Internet recovery: freezes overnight.
Making installation media: too slow/Mojave issues
Purchasing installation media: ($13) installation hangs

Nothing is working. HOURS HAVE BEEN SPENT! What else could be wrong?

I am trying another hard drive (7200) I have lying around just to rule out the hard drive.

Thank you so much for your assistance!
 

tdubbed

macrumors newbie
Sep 9, 2019
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UPDATE

I tried the same process with a known good 7200 mechanical drive I had around, and the installation got to 2 minutes overnight, but it was stuck there.

Could this be RAM related? The recovery environment is very slow, but I'm not sure if it's uncharacteristically slow.

Sata cable?

Looks like I may have to dismantle this thing even further...
 

Fishrrman

macrumors P6
Feb 20, 2009
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An important question:
Does the 2012 iMac you have, have USB3?
(I understand that some early 2012 models did not have it...)

If it DOES have USB3, the answer is as simple as it gets:
Buy a USB3 EXTERNAL SSD (such as the Samsung t5 or Sandisk Extreme), connect it, then set it up to become your boot drive.

This IS EASY TO DO, anyone can do it. If I can do it, YOU can do it.
It will TRANSFORM the performance of the iMac.
You'll come back to this thread and say, "I didn't think it could be this good!"

Regarding the internal drive:
It might be a hardware failure, or it could be software-related.
Once you have your external boot SSD up-and-running, you might consider ERASING the internal drive, running Disk Utility's repair disk feature on it, and observe the results.
Do you get "a good report"?
If so, I'd REPEAT the test about 5 times in succession.
If you get a good report every time, I'd set up the internal to become "a backup".
That way, if you ever have problems with the external drive (you're never going to have "any problems", right???), it's a 60-second procedure to boot and run from the internal drive (even though a 5400rpm platter-based drive will seem slow compared to the SSD).

If you come to the conclusion that the internal drive is damaged:
I would try to erase it with Disk Utility, and then...
...I'd just leave it there, unused.
And run everything from my external boot drive.

You could also open up the iMac and replace the drive, but you have to be sure of what you're doing.
Things are easily broken inside, and you could end up with more "problems" than just a balky drive.
 

tdubbed

macrumors newbie
Sep 9, 2019
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I can certainly set up an external SSD. I'll have to verify if it has USB 3.0 or not. I have no doubt that it is an easy task. I'll give it a shot later.

I doubt it's a hard drive failure.. maybe another piece of hardware. Every hard drive I try is slower than a snail at installing Mojave, and the installation process ultimately fails. I have run Disk Utility several times. Regardless of SSD or mechanical (7200rpm) drive, the installation fails.

I already have the screen off. I am quite adept at computer repair. I repair them and fiddle with the for a living, but this is just driving me crazy. Everything I have tried has failed.

I think I'll have to check the RAM next, which involves further disassembly.

Thanks.
 
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EugW

macrumors 604
Jun 18, 2017
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Yes, on hard drives, Mojave is a very slow to install. Also, the Mojave install process seems flaky to me.

Since you already have an SSD, trying running it off USB 3, making sure it has enough power. (All 2012 iMacs have USB 3.) If it's something like a Samsung T5, it should be fine off USB power, but if it's a different one, USB power alone may be problematic.

Once you've confirmed Mojave will install on and run off the USB SSD, you can either leave it as is, or else install an internal SSD. Note that if the install is on a regular SATA SSD, you can simply install that into the computer, without having to re-install the OS. In fact, you can take a SATA drive from another Mac and just install it in your iMac, and boot off the existing OS install on that drive.

If that still doesn't work, then perhaps it's your hard drive connector or something like that. RAM can be checked with memtest.
 

tdubbed

macrumors newbie
Sep 9, 2019
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Yes, on hard drives, Mojave is a very slow to install. Also, the Mojave install process seems flaky to me.

Since you already have an SSD, trying running it off USB 3, making sure it has enough power. (All 2012 iMacs have USB 3.) If it's something like a Samsung T5, it should be fine off USB power, but if it's a different one, USB power alone may be problematic.

Once you've confirmed Mojave will install on and run off the USB SSD, you can either leave it as is, or else install an internal SSD. Note that if the install is on a regular SATA SSD, you can simply install that into the computer, without having to re-install the OS. In fact, you can take a SATA drive from another Mac and just install it in your iMac, and boot off the existing OS install on that drive.

If that still doesn't work, then perhaps it's your hard drive connector or something like that. RAM can be checked with memtest.
Flaky for sure. I've tried three different methods to no avail.

I'll throw this SSD into an enclosure when I get home. I have a ~10 year old Crucial SSD. We'll see what happens.

Great idea about putting the SSD back into the computer!

At the very least, installing to an external will remove the internal SATA bus from the equation.

Thank you for the helpful ideas.
 

tdubbed

macrumors newbie
Sep 9, 2019
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*UPDATE*

Still in the same situation. This iMac is not handling life at this point. Extremely sluggish.

I attempted to install macOS onto my external SSD. This did not work. I formatted the drive, but was met with an error message that I cannot recall at the moment.

I then attempted to install macOS onto a traditional notebook hard drive, inserted into the iMac, I had lying around. This took a very long time, but macOS installed. Sloooooooowwww still.

I took the hard drive out and placed it into an external enclosure. This worked, and I was able to boot, but the slothlike performance remained.

Lastly, I ran a memtest86 test, and all checked out fine.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I do not think this is a hard drive issue.

Could my recovery partition be corrupted? The thing is, macOS, once booted, is as slow as the recovery environment is... could this be a graphics card problem?

Mojave... I have read reports that Mojave is running slower on older Macs. So, I have downloaded High Sierra, and I will be attempting to install it tonight.

Fingers crossed.
 

Fried Chicken

macrumors 6502a
Jun 11, 2011
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I assume you’ve done NVRAM and PRAM resets?

I think recovery partition on the bad drive is the culprit. Try making an external USB boot thing
 
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tdubbed

macrumors newbie
Sep 9, 2019
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I assume you’ve done NVRAM and PRAM resets?

I think recovery partition on the bad drive is the culprit. Try making an external USB boot thing
But is the recovery partition stored on the hard drive or in onboard flash memory? Must be onboard memory because I can reach the recovery partition without an internal hard drive present.
 

Fried Chicken

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Jun 11, 2011
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But is the recovery partition stored on the hard drive or in onboard flash memory? Must be onboard memory because I can reach the recovery partition without an internal hard drive present.
What “onboard flash memory”? The fusion drive?
 

tdubbed

macrumors newbie
Sep 9, 2019
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What “onboard flash memory”? The fusion drive?
Basically, a partition separate from the hard drive. I thought I was able to boot into the recovery partition without a drive present, but I may be mistaken. I'll check tonight.

I'm seeing the same issue via multiple websites: late 2012 Mac sluggish.. I can't help but feel that some planned obsolescence is the culprit, but, of course, that's just conjecture.

My first foray into the Mac is a sad one. I have laptops here from 2008 with SSD and a light Linux distro that fly compared to this iMac. None of this makes any sense unless there is an issue unrelated to the hard drive and RAM.

I'll keep plugging away tonight. I am not optimistic.

Thanks.
 

esatamacmodular

macrumors member
Nov 27, 2014
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I thought that USB 3.0 on the 2012 will only work at USB 2.0 speeds if using as an external boot drive. Or is that only for encrypted external boot drives?
 

Fried Chicken

macrumors 6502a
Jun 11, 2011
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Basically, a partition separate from the hard drive. I thought I was able to boot into the recovery partition without a drive present, but I may be mistaken. I'll check tonight.

I'm seeing the same issue via multiple websites: late 2012 Mac sluggish.. I can't help but feel that some planned obsolescence is the culprit, but, of course, that's just conjecture.

My first foray into the Mac is a sad one. I have laptops here from 2008 with SSD and a light Linux distro that fly compared to this iMac. None of this makes any sense unless there is an issue unrelated to the hard drive and RAM.

I'll keep plugging away tonight. I am not optimistic.

Thanks.
A partition on a Hard Drive, or any disk, is just a virtual separation. The recovery partition sits on the same physical drive as the where the OS is installed.

Make an external USB bootable drive somehow (maybe use a separate Mac), and boot up from that (hold alt/option when booting). Then install on a new Hard Drive/SSD.

Regarding slowing down. Apple didn’t build anything into their iMacs to slow them down, they just made a stupid design that makes cleaning out dust stupidly hard for the end user. You may also want to re-apply thermal paste.
 

tdubbed

macrumors newbie
Sep 9, 2019
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A partition on a Hard Drive, or any disk, is just a virtual separation. The recovery partition sits on the same physical drive as the where the OS is installed.

Make an external USB bootable drive somehow (maybe use a separate Mac), and boot up from that (hold alt/option when booting). Then install on a new Hard Drive/SSD.

Regarding slowing down. Apple didn’t build anything into their iMacs to slow them down, they just made a stupid design that makes cleaning out dust stupidly hard for the end user. You may also want to re-apply thermal paste.
Yeah, installation onto the SSD hangs. Left if overnight on several occasions only to come back to a stalled install. The only installation that has worked so far is onto a working 7200 rpm drive. It's just as slow as the stock 5400 drive.

I'm sure Apple doesn't design products that expire. Just my frustrations coming out. I can't believe how much more involved this has become than the myriad Windows/Linux based desktops and laptops I've disassembled/reassembled. I chalk it up to decades of experience with one over the other, but this is quite a painful, if rare, experience.

I'll be attempting to install High Sierra onto the SSD tonight to see what happens.

The assistance is much appreciated. Thank you.
 

tdubbed

macrumors newbie
Sep 9, 2019
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Yeah, installation onto the SSD hangs. Left if overnight on several occasions only to come back to a stalled install. The only installation that has worked so far is onto a working 7200 rpm drive. It's just as slow as the stock 5400 drive.

I'm sure Apple doesn't design products that expire. Just my frustrations coming out. I can't believe how much more involved this has become than the myriad Windows/Linux based desktops and laptops I've disassembled/reassembled. I chalk it up to decades of experience with one over the other, but this is quite a painful, if rare, experience.

I'll be attempting to install High Sierra onto the SSD tonight to see what happens.

The assistance is much appreciated. Thank you.
Starting from the beginning, can anyone shed light on this 2Gb base image? Can/should this be erased?

https://drive.google.com/file/d/18MswfscDbHPzBoMYVnLpSjdQQpGp4f0M/view?usp=drivesdk
 

barnyard

macrumors member
Jul 19, 2010
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I can't install any system updates. Any attempt at a security update or a system upgrade crashes during the update. I'll be on High Sierra for life. (2012 iMac w/ repaired fusion drive)
 

McScooby

macrumors 6502a
Oct 15, 2005
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The Paps of Glenn Close, Scotland.
My 2012 mac mini server (2TB w/ 4GB RAM) was fine til I installed Mojave & it ran dog slow, like really lose the will to live slow, beach balling galore. 16GB RAM update & external SSD & it's flying again, I'm assuming you're run Disk First Aid & Apple Hardware Test?

Just a thought is the drive completely clear apart from the MacOS install, you have 1TB free?
 
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DeltaMac

macrumors G3
Jul 30, 2003
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Starting from the beginning, can anyone shed light on this 2Gb base image? Can/should this be erased?

https://drive.google.com/file/d/18MswfscDbHPzBoMYVnLpSjdQQpGp4f0M/view?usp=drivesdk
That disk image is not useful to you. It is provided by the installer, while you are booted to that installer, and is simply part of the installer process.
It is NOT your recovery partition, if that is what you are asking.

How much RAM is installed in your iMac?
Have you tried booting to a system installed on an external drive, and NO internal drive installed?
 

tdubbed

macrumors newbie
Sep 9, 2019
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That disk image is not useful to you. It is provided by the installer, while you are booted to that installer, and is simply part of the installer process.
It is NOT your recovery partition, if that is what you are asking.

How much RAM is installed in your iMac?
Have you tried booting to a system installed on an external drive, and NO internal drive installed?
Ah, okay. Good to know I can delete that.

I have booted to a system installed on an external drive without internal drive installed.

Right now I am trying to install Mojave with my SSD formatted as APFS (I have no reasoning behind that decision to use APFS other than I hadn't tried it yet), and the dumb thing is stuck at "Estimating time remaining..."

I imagine I'll be waking up to the same in the AM. Sigh.
 

Soondae

macrumors member
May 22, 2012
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Hua Hin, Thailand
My late 2012 27" iMac died two weeks ago, local iCare technician here in Thailand told me it is the motherboard. I have a replacement motherboard in route from the states, crossing my fingers that it'll fix it.

In your case since you have it apart I would remove the CPU heatsink, clean the conductive paste from the CPU and the heatsink, apply new paste reassemble, it might fix your issue. I've resurrected many a PC with that simple process.
 

DeltaMac

macrumors G3
Jul 30, 2003
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Ah, okay. Good to know I can delete that.

I have booted to a system installed on an external drive without internal drive installed.

Right now I am trying to install Mojave with my SSD formatted as APFS (I have no reasoning behind that decision to use APFS other than I hadn't tried it yet), and the dumb thing is stuck at "Estimating time remaining..."...
I doubt that you can delete that extra drive image, as it is part or the configuration of the installer. And, because it is simply a virtual drive (not on your hard drive at all), then it makes no difference if you remove it, or not. I'm just saying that you can ignore that. It won't be there in your normal system boot.
But, good - If it boots up nicely from the external drive (without an internal drive installed), then you can assume there is something wrong with the internal bus, maybe:
- faulty SATA cable, making it challenging to boot to anything properly if any kind of an internal drive is attached.
- something ELSE attached to the SATA bus. You have two SATA connections. One is unused unless there is an SSD storage card installed (There will be both a spinning hard drive AND an SSD card installed to make up a fusion drive. Is this a possibility on your iMac? If yes, the serial number label on the bottom of the stand would tell you that it came with a fusion drive. Both devices would appear on the SATA bus on a 2012 iMac.
 

tdubbed

macrumors newbie
Sep 9, 2019
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Okay! Mojave installed itself overnight (finally), but I had ZERO time to even so much as touch the mouse.

I still think the problem will be there. My optimism is at an all time low with this thing, but I will find out tonight. If the problem persists, I'll assume something worse is the matter.

My late 2012 27" iMac died two weeks ago, local iCare technician here in Thailand told me it is the motherboard. I have a replacement motherboard in route from the states, crossing my fingers that it'll fix it.

In your case since you have it apart I would remove the CPU heatsink, clean the conductive paste from the CPU and the heatsink, apply new paste reassemble, it might fix your issue. I've resurrected many a PC with that simple process.
This is exactly what I'm suspecting is the issue, but I'll have to find out how responsive the system is when I get home later. I fear that the sluggishness will persist in spite of the SSD replacement. We will see. I'll definitely upgrade/update the thermal paste next.

How much did that replacement cost you? Good luck! PM me when you get it in and let me know if it worked for you.

I doubt that you can delete that extra drive image, as it is part or the configuration of the installer. And, because it is simply a virtual drive (not on your hard drive at all), then it makes no difference if you remove it, or not. I'm just saying that you can ignore that. It won't be there in your normal system boot.
But, good - If it boots up nicely from the external drive (without an internal drive installed), then you can assume there is something wrong with the internal bus, maybe:
- faulty SATA cable, making it challenging to boot to anything properly if any kind of an internal drive is attached.
- something ELSE attached to the SATA bus. You have two SATA connections. One is unused unless there is an SSD storage card installed (There will be both a spinning hard drive AND an SSD card installed to make up a fusion drive. Is this a possibility on your iMac? If yes, the serial number label on the bottom of the stand would tell you that it came with a fusion drive. Both devices would appear on the SATA bus on a 2012 iMac.
Roger that. I'll ignore. I did think the SATA bus could be a problem, but an external drive produced the same performance, unfortunately. Hopefully this iMac is singing happily when I return home.

Fusion drive... according to a couple of websites, and some Google image sleuthing, it looks like I do not have a fusion drive.
 

tdubbed

macrumors newbie
Sep 9, 2019
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Okay, much faster with the SSD, but... The issue is not resolved. Mouse movement is slow. Applications open faster, but 15-20 second load times.

https://drive.google.com/file/d/1YHUn4ExSizU2od_lOnDm8JJHd0S4PZ0n/view?usp=drivesdk

CPU usage averages above 90% almost constantly. Fan speed is maxed out at 3400rpm. CPU is at 31 Celsius. kernel_task is constantly utilizing anywhere from 275-450% (wut?) of the CPU.

Any idea what would cause this?

Getting closer...
 

DeltaMac

macrumors G3
Jul 30, 2003
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Try doing both resets - SMC, and NVRAM.
For your iMac, the SMC reset is simply unplugging the power cord (also unplug any other device attached that might feed power back into the iMac, like a printer, etc.) Just leave unplugged for 15 seconds, then plug power back in. Don't press the power button until after you plug in power. But, I would then go directly to the ---
NVRAM reset:
Power off, then press and hold Command-Option-P-R
You will hear the boot chime. Keep holding the same 4 keys until you hear the boot chime 2 more times, then release the keys to allow a normal boot. The NVRAM reset will reset the boot drive selection, so after boot, go to System Preferences/Startup Disk pane, and re-select your boot drive.
I know it may seem odd, but the NVRAM reset can fix that weird high-CPU symptom, and is a simple tip that you can try (and at least rule it out). Hope it fixes your issue.
 

Fishrrman

macrumors P6
Feb 20, 2009
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OP:

Go to the "users & groups" pref pane.
Create a NEW account and give it administrator privileges.
But don't put anything "in it" -- just leave it "bare bones".
Now... log out of your regular account, and log into the new account.
Try a restart, too.
Still lagging...?