27 iMac (2012) crashes and requires smc reset to turn on

I have the same iMac and the same problem. Mine was fine until I installed a bad RAM, since then I have problems with my iMac shutting down when it goes to sleep or having troubles powering on without the SMC reset. Mine requires several minutes unplugged in order to start and sometimes it needs multiple tries.

Its currently in a service at an Apple reseller in my country. I will come back and let you know their diagnostic and what needs to be done. The thing that worries me s that one guy here had the logic board replaced twice and the power supply once and it still does it!!!

If fixing whatever the repair shop tells me doesn't solve it I will go at an apple store in italy for them to fix it.

However it goes I will be back and let you guys know. Make sure everyone comes back and updates this thread if they solved the issue.

An update to my previous post:

I am fortunate that I purchased AppleCare. The Senior Advisor I have been working with had me collect system log data that has been forwarded to Engineering. The Senior Advisor has been committed to working with me on this issue. I will update again when I have something new.

Mine got back from the service provider and passed all tests, they said that unplugging and replugging 10 times worked and my iMac is not shutting down while on sleep. I am absolutely positive its a RAM issue. I had this problem while combining other OEM ram with my original ones, after a lot of testing I developed the problem. After I reinstalled the original ram that came with my mac, 8gb, it seems to work again. I think ram slots count as well, I mean you should left the ram in the slots it came in. Very strange behavior, I will test it further more and report.

I can at least address iForce's question; it might be best to post in separate threads to get your individual questions answered with the care they deserve.

In the meantime, do an Entrecheck run and post your results in this thread. If you don't have Entrecheck, you can download it free here:

http://www.etresoft.com/etrecheck

Just a small update for everyone... Since installing CUDA and the recent Apple OS updates I've not had any shutdowns for about the last 2 weeks. I hope the same is true for everyone else with this problem.

Sounds interesting, but I have no command line experience 😐

Here's the link and the NVIDIA GeForce GTX 675MX (iMac late 2012 i7) seems to be supported - link:

http://docs.nvidia.com/cuda/cuda-getting-started-guide-for-mac-os-x/

If anyone has or knows of a simplified step by step guide for the uninitiated that would be helpful.😕

Same issue here; random shutdown without warning. No rhyme or reason.

late 2012 iMac 27"

3.4 intel i7

4GB Ram

GTX 680

Took to Genius bar. They had it for over a month. They replaced power supply, logic board $800. Took it home worked for two weeks without issue. Then started same symptoms all over again. I check the logs, nothing. Run the Apple hardware test, no errors. tested the ram with Rember, no errors, & run EtreCheck, nothing stands out as to the cause of this issue. Sometimes I'll be browsing with chrome or safari..shuts down. Sometimes, it shuts down while booting up! Unplug it for 15 seconds, do nothing for 10 more seconds, power on.

Really at my wits end with this iMac, this is likely my last. Really annoyed, considering I basically paid 1/3 of a new iMac to "fix" it...

Here is the Etrecheck below:

EtreCheck version: 2.2 (132)

Report generated 7/18/15, 3:09 PM

Download EtreCheck from http://etresoft.com/etrecheck

Click the [Click for support] links for help with non-Apple products.

Click the [Click for details] links for more information about that line.

Hardware Information: ℹ️

iMac (27-inch, Late 2012) (Technical Specifications)

iMac - model: iMac13,2

1 3.4 GHz Intel Core i7 CPU: 4-core

4 GB RAM Upgradeable

BANK 0/DIMM0

2 GB DDR3 1333 MHz ok

BANK 1/DIMM0

2 GB DDR3 1333 MHz ok

BANK 0/DIMM1

Empty

BANK 1/DIMM1

Empty

Bluetooth: Good - Handoff/Airdrop2 supported

Wireless: en1: 802.11 a/b/g/n

Video Information: ℹ️

NVIDIA GeForce GTX 680MX - VRAM: 2048 MB

iMac 2560 x 1440

System Software: ℹ️

OS X 10.10.4 (14E46) - Time since boot: 0:3:15

Disk Information: ℹ️

APPLE HDD WDC WD10EALX-408EA0 disk0 : (1 TB)

EFI (disk0s1) <not mounted> : 210 MB

Macintosh HD (disk0s2) / : 999.35 GB (699.76 GB free)

Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB

USB Information: ℹ️

Apple Inc. FaceTime HD Camera (Built-in)

Apple Inc. BRCM20702 Hub

Apple Inc. Bluetooth USB Host Controller

Thunderbolt Information: ℹ️

Apple Inc. thunderbolt_bus

Gatekeeper: ℹ️

Mac App Store and identified developers

Kernel Extensions: ℹ️

/Applications/Parallels Desktop.app

[not loaded] com.parallels.kext.hypervisor (10.2.1 29006 - SDK 10.7) [Click for support]

[not loaded] com.parallels.kext.netbridge (10.2.1 29006 - SDK 10.7) [Click for support]

[not loaded] com.parallels.kext.usbconnect (10.2.1 29006 - SDK 10.7) [Click for support]

[not loaded] com.parallels.kext.vnic (10.2.1 29006 - SDK 10.7) [Click for support]

/System/Library/Extensions

[loaded] com.avira.kext.FileAccessControl (1.0.0d1 - SDK 10.9) [Click for support]

[loaded] com.nvidia.CUDA (1.1.0) [Click for support]

Launch Agents: ℹ️

[loaded] com.avira.antivirus.general.agent.plist [Click for support]

[loaded] com.avira.antivirus.ipm.ui.plist [Click for support]

[loaded] com.avira.antivirus.notifications.agent.plist [Click for support]

[loaded] com.avira.antivirus.odscan.default.plist [Click for support]

[loaded] com.avira.antivirus.scheduler.agent.plist [Click for support]

[running] com.avira.antivirus.systray.plist [Click for support]

[loaded] com.avira.antivirus.telemetry.agent.plist [Click for support]

[loaded] com.avira.antivirus.update.default.plist [Click for support]

[running] com.avira.helper.avstats.plist [Click for support]

[loaded] com.nvidia.CUDASoftwareUpdate.plist [Click for support]

Launch Daemons: ℹ️

[running] com.adobe.ARM.[...].plist [Click for support]

[loaded] com.adobe.fpsaud.plist [Click for support]

[loaded] com.avira.antivirus.dbcleaner.plist [Click for support]

[failed] com.avira.antivirus.ipm.loader.plist [Click for support]

[running] com.avira.helper.watchdox.plist [Click for support]

[loaded] com.nvidia.cuda.launcher.plist [Click for support]

User Launch Agents: ℹ️

[loaded] com.adobe.ARM.[...].plist [Click for support]

[loaded] com.google.keystone.agent.plist [Click for support]

[loaded] com.valvesoftware.steamclean.plist [Click for support]

User Login Items: ℹ️

Steam Application (/Applications/Steam.app)

iTunesHelper Application (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)

Degrees UNKNOWN (missing value)

AdobeResourceSynchronizer Application Hidden (/Applications/Adobe Reader.app/Contents/Support/AdobeResourceSynchronizer.app)

Internet Plug-ins: ℹ️

FlashPlayer-10.6: Version: 18.0.0.209 - SDK 10.6 [Click for support]

QuickTime Plugin: Version: 7.7.3

AdobePDFViewerNPAPI: Version: 11.0.12 - SDK 10.6 [Click for support]

AdobePDFViewer: Version: 11.0.12 - SDK 10.6 [Click for support]

Flash Player: Version: 18.0.0.209 - SDK 10.6 [Click for support]

Default Browser: Version: 600 - SDK 10.10

F5 SSL VPN Plugin: Version: 7070.2012.1026.1 [Click for support]

Safari Extensions: ℹ️

Open in Internet Explorer

3rd Party Preference Panes: ℹ️

CUDA Preferences [Click for support]

Flash Player [Click for support]

Time Machine: ℹ️

Skip System Files: NO

Mobile backups: OFF

Auto backup: NO - Auto backup turned off

Volumes being backed up:

Macintosh HD: Disk size: 999.35 GB Disk used: 299.58 GB

Destinations:

Time Capsule [Network]

Total size: 2.00 TB

Total number of backups: 66

Oldest backup: 2013-05-30 07:35:04 +0000

Last backup: 2015-06-20 03:42:00 +0000

Size of backup disk: Adequate

Backup size 2.00 TB > (Disk used 299.58 GB X 3)

Top Processes by CPU: ℹ️

44% mdworker(2)

2% WindowServer

2% fontd

0% steam_osx(2)

0% savapi

Top Processes by Memory: ℹ️

497 MB kernel_task

340 MB savapi

315 MB avguard.bin

90 MB steam_osx(2)

74 MB ocspd

Virtual Memory Information: ℹ️

548 MB Free RAM

3.46 GB Used RAM

0 B Swap Used

Diagnostics Information: ℹ️

Jul 18, 2015, 03:04:41 PM Self test - passed

Jul 18, 2015, 02:17:06 PM /Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2015-07-18-141706_[ redacted].hang

Thanks for your Entrecheck run. Here's what I learned:

1. While 4GB RAM is sufficient for many users, doubling the RAM will increase the speed and possibly the stability of your system - especially with the latest Mac OS. The fact that nearly all of the virtual RAM is used suggests you need a more physical RAM.

2. Avira Antivirus is probably unneeded, and seems to be using a lot of system resources. I'd remove Avira, preferably with an uninstaller.

Do you have any readings re: the heat on your machine? Can you post them here? iStat is a quick way to get these readings.

Yes, got another one here. Late 2012 2.9Ghz i5 27" 10.10.4.

What percentage fix rate is there for installing a new power supply and, similarly, a new logic board?

Has anyone else had success installing CUDA?

Many thanks.

Unbelievably (And just my luck), I have the same model at work, which over the last week has just started to randomly crash like my home one. As mentioned before the home mac hasn't crashed since installing CUDA, so I'm going to try the same fix on the machine at work and if successful, will post step by step of all the actions taken. Hopefully I'm right on this, but will update ASAP.

Is it just me or is there a clue in the number of units which seem to be failing in a very close time frame post manufacture?

I was wondering if there is an NVRAM power supply on the logic board.

I also have the same problem with also a late 2012 27" iMac 13,2 3.4 GHz i7, 16 Gb RAM, NVIDIA GeForce GTX 680MX 2048 Mo.

Reading several posts on this subject, I see that it happened on other iMac models, although much more often/reported on the late-2012 27" iMac.

It would be interesting to really compare our configurations.... so far I have seen only one mentioning i5 CPU.

There is another thread on the same topic here : Why is my imac shutting down by itself?

The first symptoms started for me beginning of July 2015, e.g. 2.25 years after purchase.

Things I did:

- brought it to a Mac repair: they didn't find anything, said it was a software issue, reinstalled OS X. It worked 2 weeks before starting again, and more and more frequently as reported by others.

- Downloaded and installed MacFan : http://www.crystalidea.com/macs-fan-control

to "force" the fan cooling better the inside

- Purchased and installed a physical power switch between the electrical cord and the plug: as reported in the other thread above, that seems to be the only thing that works: each time I switch off the iMac from the Apple Menu and the iMac powers off, I then physically switch off the plug. This is like resetting the SMC each time you switch the computer on. So far (2 days) symptoms have stopped.

Hey guys I do not want to jinx it but I may have found a way to fixing this random shutdown problem of iMac. As mentioned before in my post, I have a late 2012 27inch iMac and it's been randomly shutting down for the past year or so. One short term solution that I've found was to leave the iMac unplugged from power for a couple of days then reconnect. There seems to be a relationship between the longer the period of unplugged time, the longer it will stay up before crashing. A few days ago I decided to factory reset my iMac. I've backed up using Time Machine just right before it. Surprisingly, the iMac hasn't crashed since yet. I do not know if anyone has attempted this method yet but hopefully this solves the issue. I've also installed CUDA when smithy_dave posted that it might solve the issue. But anyways, let me know if anyone's iMac show the same result after factory resetting! Good Luck! 🙂

I'm almost certain its graphics card related, the CUDA installation, coupled with making sure all apps are upto date seems to have significantly reduced the number of crashes / random shut downs. this is true for the two machines I have access too, I have however experienced one shut down in the last 14 days or so, however this is more bearable then the several a day I was getting and could be unrelated. it would be great to see if anyone else noticed this improvement with CUDA install.

Count one more. Same same. Last week got my iMac back from the Apple Store with a new hard drive installed as part of the iMac (27-inch) 3TB hd replacement program they've offered for computers sold between December 2012 and September 2013. I was hoping it would solve my sudden shutdown issue that began to occur sparingly last April and became more frequent. They gave the new hd a stress test before releasing it to me after finding nothing wrong. It worked fine for a week, then yesterday I experienced several "intermittent shutdowns" as they termed it. The nightmare continues.

We bought 3 similar computers at the same time for work, mine is the only one with this issue. Thank you all who have replied here offering solutions that have worked or not worked for you. Small comfort to have company in this situation but helpful to read of your similar experiences and attempts at eliminating the problem.