Imac shutting down

[Steamer Dave]

About a month ago my Imac started shutting down after about an hour. I went to Preferences-Energy saver and extended shut down. Last week in desperation I extended that to NEVER. and it still shuts down after about an hour.
When it shuts down I have to log in and wait for it to populate the desktop and all of the programs I had running have to be brought up again with all the associated rigamarole.

I have noticed that if I am away from the computer for 4 or 5 hours, when I hit the space bar several times up comes a screen that looks like a piece of fabric.. It takes several taps on the escape key to get rid of that and then to the log in screen.

Can anyone give me an inkling about what is going on and where I can go to change this?

Dave

 

[honestone]

First, what exact iMac model do you have?

Secondly, what Mac OS are you using?

Third, do you have any anti-virus software on your machine?

Fourth, do you either Mac Keeper (REAL, REAL BAD!), or CleanMyMac?

Fifth, how much free space is on your internal drive?

Sixth, are you making backups to an external device?

Finally (at least for now), have you been performing any disk cleanup/maintenance tasks, and preferably on a periodic basis?

All of that will help us provide assistance.

 

[Steamer Dave]

Imac 27

el kapitan version 10.11.1

Avast

Do not do either of those

827 GB

Yes I do back up bi weekly

Have done no disk cleanup/maintenance

 

[honestone]

OK, good information. But, need the exact designation for the iMac model you have.

First, a new version of El Capitan, V10.11.3, came out two weeks ago. You can get the Combo Updater from here:

https://support.apple.com/kb/DL1859?locale=en_US

Secondly, I gather by the amount of free space you have that there is at least a 1 TB drive inside the machine. Wonder if it is Fusion Drive "setup", and also what the rotational speed of the drive is.

Third, I am not familiar with Avast, so don't know if that presents any issues.

Fourth, for your backups, are you using Time Machine? And, no matter what you are using, are you doing it to an external drive?

Now, it is important to get into the habit of doing disk cleanup/maintenance. Do you happen to have either of the excellent third party programs TechTool Pro or Disk Warrior? Either can be of great benefit.

One excellent free program you can download is Onyx. You can get it form here:

http://www.titanium.free.fr/onyx.html

Make sure you get V 3.1.4, which is specifically for El Capitan. This product has been around quite a long time, is rock solid, and has had numerous, excellent reviews. I have been using for so long that I depend upon it. In fact, I will not do any major Mac OS upgrades (like going from Yosemite to El Capitan) until Onyx has been updated. One useful task missing in the version of Disk Utility with El Capitan is Verify and Repair Permissions. Well, Onyx has that feature, and I usually need to run it twice for each of my machines as part of my weekly disk cleanup/maintenance, and backup processing.

Assuming you only have Disk Utility, there is a hidden Recovery Partition on your machine. This link describes how to boot to that partition, and what is on it:

https://support.apple.com/en-us/HT201314

You can use Disk Utility to Verify and Repair your drive at both the Volume and Partition levels. I actually do not use that, as I have TechTool Pro, and it is superior to Disk Utility. Also, it is easier to boot to. (I also have Disk Warrior).

In your situation, as long as you are making the backups to an external device, using Disk Utility is safe.

 

[Steamer Dave]

Model Name: iMac
Model Identifier: iMac10,1
Processor Name: Intel Core 2 Duo
Processor Speed: 3.06 GHz
Number of Processors: 1
Total Number of Cores: 2
L2 Cache: 3 MB
Memory: 4 GB
Bus Speed: 1.07 GHz
Boot ROM Version: IM101.00CC.B00
SMC Version (system): 1.53f13
Serial Number (system): W800828A5PE
Hardware UUID: 509C756B-4C4F-523F-9BCC-3D4E9FFEA049

Hey, if apple doesn't announce new upgrades to users I am not clairvoint.

I have no idea about the hard drive except that it is 1 TB.

I use time machine to an external used for backup only.

WHat does all this have to do with the inability to prevent these shut downs?

 

[honestone]

Apple did "announce" it, although one needs to be vigilant in looking at various boards/sites to see such information.

Also, all of the information asked for is important for any type of plan to try and help you. Disk issues can certainly cause your problem, and especially if you have not doe any disk cleanup/maintenance. It actually seems like most folks that come here for a "cure" expect an easy one. In a few cases, that is possible. But, in most instances, it takes more effort (and tools). That is the case here.

I have to get going, and I'll be back on later. Maybe someone else might "chime in" and offer assistance. If not, I'll try and help out later.

 

[Steamer Dave]

Well, it is still shutting down and even more irritating it does not save and restore the apps that were still active. I have taken to playing music to keep it alive. The previous responder has given up.

Dave

 

[Cory Cooper]

Hello,

To me, it sounds more like it could be a hardware issue - overheating, failing hard drive, kernel panic leading to power off, etc.

-Does anything seem to trigger the shut downs, or is it random?
-What software is running when the shut downs occur?
-Have you tried an SMC reset and/or a PRAM/NVRAM reset?
-Would it be possible to take the iMac to an Apple Store near you for full hardware diagnostics?

C

 

[Steamer Dave]

The only way I can think of to find the precise time it goes into hibernation is sit in from of it and wait. I am pretty sure it is around an hour without any use. If there were hardware problems would there not be some kind of warning messages?? And if I am working one for extended periods it does not go "quiet".
If it would restore the apps I was using it would not be such a pain but I have to start sigh in and start from scratch.
I have no idea what a SMC reset is nor a PRAM/NVRAM .
I could take it to the apple store but I am hard pressed to see this as a hardware problem.

 

[Cory Cooper]

If it doesn't happen when in use, then it may not be a hardware issue. If it happens more around an hour with no use, then there may be an Energy Saver setting that is powering it off, or some other software factor. But, you stated that you adjusted those settings.

The SMC and PRAM/NVRAM resets I mentioned are actually links if you click on them, which take you to Apple's website with instructions on how to perform them. They would be the first troubleshooting steps that Apple would take, after their full hardware diagnostics.

Since you set the Energy Saver to never power off, then it may just be going into sleep mode...especially if you can login when it wakes, without hearing the startup chime and seeing the Apple logo startup screen. There could be some software causing it as well. Avast and other antivirus apps have been known to cause performance-related issues, especially if their on-access or real-time scanning is enabled.

I re-read your initial post, and you mentioned "I have noticed that if I am away from the computer for 4 or 5 hours, when I hit the space bar several times up comes a screen that looks like a piece of fabric.. It takes several taps on the escape key to get rid of that and then to the log in screen." The screen that looks like fabric, is an indicator that their may be a hardware issue with the graphics card. Does you iMac have an ATI Radeon HD graphics card in it by chance? Some users had reported issues similar to what you are experiencing.

Also, you stated you had a 1 TB hard drive...is it a Seagate? There was an Apple Repair Extension program that covered replacement of them in some iMacs sold between October 2009 and July 2011. Unfortunately, that program has since expired and they are no longer covered.

We are happy to continue to investigate, but recommend to continue your Time Machine backups, try the SMC and PRAM/NVRAM resets, and have an Apple Store look at it if at all possible for hands-on diagnosis.

C

 

[Steamer Dave]

Thanks for the tips. I will try them and see what comes up.
The hard drive was replaced in that apple recall.
I have not noticed that "fabric" screen in several weeks now.
The usual screen now seen is one where there are three options, restart, logon and sleep

Dave