You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

27-inch / 27" iMac Random Shut down

SPECS:____________________________________________________________________________
• 27" 2.8 GHz Intel Core i7 / 8gig / 1TB
• OS 10.6.3 (about to update to 10.6.4)
• All firmware updates have been applied according to software update
• 3 external drives: 1-320 gig 800fw / 1-TB USB 2.0 / 1-500gig USB 2.0

INFORMATION:____________________________________________________________________

I've been running with this configuration ( 3 extra drives) since approximately December with no issues. Out of the blue... only running Aperture and Safari - my iMac JUST SHUTS off- WITHOUTwarning. It acted as though I was running a MacBook and the battery going dead/asleep. That's how random and sudden it shut down - NO WARNING. I did have the iMac asleep for about three hours before coming back to it to start working again when it shut down, but it should have even been cool.

I only started reading around on the web to see of other incidents after this random shut down this evening, but I can't find anything specific. I've found A LOT of similar things - all seemingly related to "HEAT."

And heat seems to be a certain issue recently - in the last day or two. Today I noticed my top back side to be hot, which isn't uncommon, however, it became so hot I really wasn't able to keep my hand on the top back. I've also noticed A LOT of spinning beach balls, and lots of processor delay! Heat??

There are NO energy saver pref's set to automatically shut it down. The power was and is firmly set. There are no network settings, nor access to the iMac to have it shut down. It is not shared with anyone on the network.

SUMMARY:___________________________________________________________________________

• Today, I grabbed a couple temp / monitor widgets and am trying to watch the data. All components seem to be at/around/below 140 degrees F with ambient air at 77 degrees. I don't know numbers, but that all seems reasonable.
• Going to update to OS 10.6.4 (doubt that's it!!)
• I'm going to run the hardware test from my disc to see if ANYTHING. 8-p
• AND... I'm going to call Apple to set up a case. It's still full under warranty, and I have 2 more years of AppleCare on it. But there's been too many things pointing to hardware to call this a software issue.

I've dodged all the display issues with my iMac, but now.. I'm a bit hacked knowing how much I spent on this thing, with the initial DELAYS I went through, ordering it before it had even been released!

?? QUESTION ??_____________________________________________________________________

So, has anyone else been having this issue, heard of a solution, seen anything on Apple's website of known issues ??

Barry
( Grumbling bout my Mac)

Which one of twelve??, Mac OS X (10.5.6), ever hear Newton?!! ;-) One of those, too!

Posted on Jun 22, 2010 8:59 PM

534 replies

Nov 3, 2010 6:41 AM in response to kfiller

kfiller,

Sounds like your situation is worse than most. I'd seriously consider doing an RMA or having it exchanged at a mac store.

FYI: On the mid 2010 iMac I'm using the bluetooth keyboard and mouse that came with the iMac. No random restarts on this machine at all.

On the late 2009 iMac (both of these iMacs have i7's, btw) my coworker is using the USB version of the apple keyboard so he can use the numpad but is also using the bluetooth magic mouse. He sometimes gets random restarts but it seems to have been better over the last couple of weeks. We also noticed that when he uses Parallels 5 and leaves it running overnight the top of the iMac is noticeably hotter than if its not running and sometimes we'd come in and the iMac would be off or restarted, so we started closing Parallels before leaving for the day. Seems to have helped.

Nov 9, 2010 6:56 AM in response to Berry with an A

Hi to all. Same problems in my 27" Core i5.

Here are the complete specs :

OS : 10.6.4
Identifier : iMac 11,3
Proccesor : Core i5
Speed : 2,8Ghz
Num. of Cores : 4
Memory : 8Gb 1333Mhz ( Aftermarket GSkill 4x2Gb modules )
BootRom : IM112.0057.B00
SMC ver.: 1.59f2
HDD 1 : OCZ Vertex2 120GB SSD
HDD 2 : 1Tb ST31000528AS
Graphic Card : ATI Radeon HD 5750 1Gb

Using USB Keyboard : Yes
Using Bluetooth Mouse : Yes ( Apple Trackpad )

That's all the info i think it's useful. Most of the shutdowns are when the computer is idle, but just a while ago it just shut down when i was working.

Sometimes seems to be ok, it keeps 5 or 6 days without any shutdown, but for example, yesterday i have one and today another one.

I work with this computer, and it's very very annoying to have that kinds of shutdowns. My iMac it's about a month old.

I wish to know what apple thinks about our problem ..... :/

kfiller

Level 1

4 points

Nov 11, 2010 5:39 AM in response to SMiLEY2billion

I ended up following the advice found on another thread regarding the removal of one of the 4GB memory sticks, and replacing it with one of the original Apple 2GB sticks. Been almost week without any shutdowns. Magic? I'm knocking on wood.

It's a bit ridiculous that I have to put up with 14GB of memory when there's no good reason why 16GB initiates the auto-shutdown death mode.

In the end, this is still a problem that needs to be officially addressed. Perhaps it's best to stop posting in this thread, as it has been marked as "solved".

Nov 11, 2010 1:01 PM in response to Dextercitox

Just wondering if anyone has downloaded the new OS 10 update and whether or not it solved anyone's issues.

bsales

Level 1

4 points

Nov 11, 2010 4:43 PM in response to Malibu Flyer

We have 7 new iMacs that we are using for heavy visual effects production. Our machines have 16GB (though not currently) and we are finding the same results as others... All our machines have powered down suddenly - generally when taxed. If we reduce memory, things are fine. A prior generation iMac and numerous Mac Pros are operating just fine.

We've replaced memory through OWC with the latest NuRAM (1333mhz) and it's the same situation. One machine has memory purchased from MacMall and that has the same problem.

AppleCare says it suspects our building's power is faulty. With the issues others are having and our non-iMac machines being happy I think they're incorrect. Also, every machine is on a UPS, so that should protect from everything but massive power problems.

** I just upgraded one machine to 10.6.5 and it failed immediately with a test we've developed using one of our software applications.

I'm working with OWC to try the Samsung memory that they sell. That's the only thing I've heard has helped others. Any other suggestions would be appreciated.

THIS IS A SIGNIFICANT ISSUE THAT APPLE NEEDS TO ADDRESS ASAP

Thanks

Nov 11, 2010 6:46 PM in response to Berry with an A

I also just ran into this issue. Bought the iMac (i7, maxed out) two weeks ago. So far it has shut down twice. (And because bad luck never comes alone, my brand new MacBook air that was ordered at the same time, has frozen with a blank screen four times so far.)

kfiller

Level 1

4 points

Nov 13, 2010 10:02 PM in response to kfiller

Knocking on wood did not help - I just experienced another shutdown, this time with 14GB of memoru. Browsing the web using firefox, nothing else open. iPhone 4 was connected to the machine

A couple of things to note -

*-- switching to 14GB does NOT solve the problem. It just seems to make the shutdown happen less frequency.*

*-- Every so often I reboot into Win7-x64 to get some office work done. I so far have not experienced a shutdown in Win7.*

I'm running out of ideas, and just about ready to pack everything up and return it to the Apple store. 😟

Nov 14, 2010 7:08 AM in response to Berry with an A

Bummer, this is a discouraging thread. My 8 year old iMac (just died) suffered from an unexpected shutdown problem that turned out to be a power supply issue. In researching the issue, I learned that Apple knew about the problem before they shipped, but decided to deal with the issue in warranty repairs. In fairness to Apple, they extended the warranty on that issue. Was still a big problem for me, as we had no warranty service here during most of the life of my Mac.

Now that I need a new Mac, I'm sorry to hear these kinds of problems are still happening with iMacs eight years later.

Here's one proposed solution. You probably won't like it, but I sincerely feel this is the only real solution.

First, for any Mac still under warranty, Apple should pay us an hourly rate for dealing with any problem that can be documented to be a failure of Apple hardware. This would make shipping broken computers (defined as a computer that dies during warranty) an unprofitable enterprise.

Ok, Apple won't agree with this, so it's on to Step Two.

Do we really need a new Mac? Really?

I'm typing this on a 15 year G4 that's worth about $50. This machine works just fine for the vast majority of tasks most people buy computers for.

So, what I'm suggesting is this. If you are serious about helping Apple become a true quality provider, don't buy a new Mac unless you really one, UNTIL Apple stops shipping Macs that die during warranty, OR they pay us for dealing with THEIR problems.

Imho, there's no real point to Apple's existence unless it can be a quality alternative to the PC world. Part of being a quality alternative is shipping Macs that don't burden users with failures during warranty.

Ok, I'm realistic. I know that you won't agree, and will now tell me a hundred reasons why this can't happen etc. Ok, fair enough.

But it is simply a fact, that as long as we accept the status quo, none of us will know whether buying a new Mac will make us the next person in this thread wrestling with their new Mac, and Apple's response.

Moral Of This Story: Think bigger.

Stop trying to solve the all the details of technical problems. Stop working for Apple for free.

Instead, address the problem at it's source, the business problem.

Apple is willing to sell us stuff it knows is broken, and we're willing to buy it. That's the real problem.

JDI

Level 1

0 points

Nov 14, 2010 8:56 AM in response to Berry with an A

I am also having the same problem- I am running an 11 month old 27 inch I5 Imac with 8 gigs of memory- 2 are Crucial. The MAC will either restart spontaneously or shut down in the middle of work
After running the 10.6.5 update I have been okay for a few days. I have not yet used Parallels- see below.

I have found that my problems usually occur after using Parallels. I am using Parallels 5 Build 5.0.9376 with Windows 7. I am a light duty user on the Windows side, using it for only Quickbooks. I always back up with a Sandisk USB Key. I put the key in while Windows 7 is running and remove it "by the book." after I use it.
My thought is could this be corrupting the SMC?
I would like to know if others are having problems while doing similar tasks?

Pinthea

Level 1

20 points

Nov 15, 2010 7:44 AM in response to JDI

Mid-2010 Corei7 iMac originally shipped with 4GB RAM. Immediately upgraded it to 8GB ram by adding 2GB of OWC DDR3-1333 Memory. Ran flawlessly since.

Last week I ordered 16GB (4x4GB) of NuRAM from OWC. Carefully swapped it out (being careful about static discharge, as usual).

Ran fine for a day, next day (Saturday morning) came in to the home office and found the machine was mysteriously off. Shrugged shoulders. Turned it on, worked fine. Though it was time to reformat and reinstall anyway, did that Saturday evening.

So I erased and reinstalled 10.6.4 from scratch, copied over my data files from my external hard drive, reinstalled my apps (basic stuff, like iWork) hoping a fresh install would solve the unexpected power-off. I am not using Parallels.

Last night (Sunday) I went to the machine to use it, it had just been sitting there idle for hours, not doing anything. Jiggled the mouse, display came on as expected, then tried to launch Safari, BLAMMO, the machine suddenly powered off. As if someone pulled the plug.

Turned machine back on, booted fine, no problems.

So I immediately rebooted into Apple Hardware Test, ran full/complete test overnight, said "No problems" this morning.

Bummed that my 16GB upgrade is like yours -- causing random power-offs.

Probably going to have to get with OWC to return the memory given these apparent problems with the iMac i7 and 16GB. What a shame, Apple. You disappoint me.

I was going to try to remove and re-seat the memory, but after reading this thread I'm thinking it won't help.

Nov 19, 2010 9:02 AM in response to Berry with an A

So Nov 2, I believe was my last post, when we pulled out 2 RAM sticks, dropping my memory to 8GB. I've had zero shutdowns since.

In reading through posts and remedies tried, it seems–correct me if I'm wrong–that everyone who has the crashes has all four slots filled with equal-sized chips. People who run 12GB via 4 chips seem to have found a remedy, and people using only two chips seem to have found a remedy (myself included).

Just trying to pinpoint the issue a bit more so WHEN Apple decides to acknowledge this problem, they have something with which to work.

Nov 19, 2010 1:05 PM in response to Berry with an A

Incredible. Just incredible.

After 9 days without any shutdown, just 20 minutes ago i had 4 shutdowns in a row ....

But the most incredible, is that i can reproduce it every time i want !!! ...

That's the way to reproduce :
- Open Photoshop CS5.
- Open two images, copy one and paste inside the other.
- Transform the image, clicking option shiftleft click and drag .... ( just options to scale from the center and without distort )

After that, it shutdown inmediatly ....

I have try it 5 times more, and 5 shutdowns. For the curious, when i restart Photoshop after reboot, a message appears saying "There was a problem with your GPU and the acceleration has been disabled ...." ( more or less, i'm spanish ... )

I'm using the Magic Track Pad and a USB keyboard, some user before commented that could be related with bluetooth keyboards or mouses, perhaps he is correct.

I have 8GB, and i dont believe that the problem is in the amount of memory, the problem perhaps is related with the amount of banks used ( i use 4 2Gb modules), but .... ¿ Why i can shut down it with my keyboard and trackpad ?

😟

foh

Level 1

0 points

Nov 24, 2010 2:41 AM in response to Dextercitox

I basically have the smae problem. I have a 27" iMac which I bought with 4gb then added another 2 stick of 4gb each to make it 8gb. That was when the random shutdown happened. Well its not random anymore coz it only happens to me when I transform smart object layer while holding the shift key. So far since the OS update it hasn't shut down on me.. yet..

kfiller

Level 1

4 points

Nov 24, 2010 3:34 AM in response to kfiller

Some more news to report from my side, as it's been a few days since the last update:

+ Moved to 12GB, 4x2 Corsair sticks, 2x2 Samsung oem sticks. Experienced 2 shutdowns in the span of a few hours yesterday.

+ Disabled all bluetooth devices, switched to USB keyboard/mouse. No effect.

+ Fed up, I made a run to the local Apple store with the iMac in tow. Sat there explaining how I did everything under the sun to diagnose the problem, but still could not come up with a definite reason on why/how the machine just kept turning off. As expected, the problem did not occur when the Apple technician was looking for it.

+ In the end, the Apple tech seemed to take pity on my situation, and said that they would be able to offer a full exchange to a new machine.

+ I just ordered some OEM Samsung memory (16GB) to swap out my Corsair, wIll report back if this helps or not.

Finally, just one request for those that are new to the thread and having shutdown problems: please post your memory configuration (size + maker)...

Cheers

Nov 24, 2010 4:20 AM in response to kfiller

The problem, is not the total amount of memory, is the banks used.

With 8Gb, 12Gb or 16Gb, if you use all the banks, the problem seems to appear.

If you have 8Gb, but using only 2 banks, seems to be no problem.

I can also shutdown my mac using the keyboard and trackpad, scaling a image.

27-inch / 27" iMac Random Shut down