13 Replies Latest reply: Oct 30, 2012 10:57 AM by nomadic.lucy
nomadic.lucy Level 1 Level 1 (0 points)



I've been having problems with my Mac freezing.  I've tried all kinds of things (verify and repair permissions and disk etc, make sure enough free space, as well as checking fans, disk utility etc) and the problem persists.  It's a 24inch iMac that I bought in late 2008 and the problems have been  ongoing intermittently for  months now.  Basically what will happen is  that I’ll be using it when it will suddenly freeze and the screen goes  blank.  The only thing that works then is to restart by holding down the  power button on the back to turn it off and then on again.  I use it  most often for internet (I use firefox) but the issue has happened when  doing other things too, so I don’t think it’s related to any particular  programme.


I took it into the genius bar and after checking the disks and finding no problem their advice was to reinstall snow leopard.  I was the last appointment of the day before a long weekend and the guy was helpful but fairly rushed.  The thing is that I had this problem with leopard as well before upgrading to snow leopard, so I can't see how it's related to snow leopard.  So, is reinstalling snow leopard likely to help?  Would it be easier to upgrade now to Mountain Lion instead and see if that helps?


Any suggestions gratefully accepted and please let me know if there's other information that you would need to know in order to provide any suggestions.


Thanks so much in advance


Model Name: iMac

Model Identifier: iMac8,1

L2 Cache: 6

iMac, Mac OS X (10.6.8)
  • nomadic.lucy Level 1 Level 1 (0 points)

    I'd be really grateful if someone had guidance to offer!


    Just in case the added details are useful:


    Hardware Overview:

      Model Name:    iMac

      Model Identifier:    iMac8,1

      Processor Name:    Intel Core 2 Duo

      Processor Speed:    2.8 GHz

      Number Of Processors:    1

      Total Number Of Cores:    2

      L2 Cache:    6 MB

      Memory:    2 GB

      Bus Speed:    1.07 GHz

      Boot ROM Version:    IM81.00C1.B00

      SMC Version (system):    1.30f1

  • R C-R Level 6 Level 6 (16,875 points)

    I have the same model. What I suggest you try next for this problem:


    1. Run the Apple Hardware Test. It can't detect all hardware problems, especially intermittent ones like you might be having, but it is still a good first step.


    2. Reset the SMC. I'm not sure why but this has fixed some odd problems I have had in the past with my 2008 iMac.


    3. If this doesn't help, try running for a while without any peripherals attached to your iMac besides the keyboard & mouse. If you don't see any freezing problems, try reattaching your other peripherals one by one & running that configuration long enough to see if one of them is causing your problems.


    4. If none of this helps, go ahead & reinstall Snow Leopard, making sure you run Software Update afterwards to update it to the latest version. The Snow Leopard installer isn't like earlier OS installers. To reinstall the system just run it & accept the defaults. It won't write over or alter your user data or create any "Previous System" folder stuff, so it is a fairly painless procedure. It even performs the equivalent of Disk Utility's verify disk step, so you don't have to do that beforehand.


    5. If none of this helps, reply to this topic & we can suggest other things to try.

  • nomadic.lucy Level 1 Level 1 (0 points)

    Thanks so much for your help!  I'm going to try all of these steps over the next day or two and will let you know how I get on... Fingers crossed!

  • nomadic.lucy Level 1 Level 1 (0 points)

    Hmm, so tried steps 1-3 above and my Mac crashed again today without warning.  I was using only firefox at the time and had no peripherals attached.  Before I go on to step 4 and reinstall Snow Leopard, can anyone advise whether I would be better to try upgrading to Mountain Lion instead, and see if that helps?  I figure I'd need to upgrade at some point anyway so might as well do it now rather than reinstall Snow Leopard?


    Advice gratefully accepted!


    Many thanks.

  • R C-R Level 6 Level 6 (16,875 points)

    Since the normal way to upgrade to Mountain Lion is through the Mac App Store, which requires running a stable version of Snow Leopard to download & install it, I stand by my suggestion to reinstall SL before doing anything else, even if you plan on upgrading to ML later.

  • nomadic.lucy Level 1 Level 1 (0 points)

    Okay - good point.  Since I had this problem before upgrading to Snow Leopard, I guess it was wishful thinking to hope that upgrading to Mountain Lion would fix it.  Will see if I can find the SL disk and reinstall.  Thanks for your help.  Fingers crossed!

  • nomadic.lucy Level 1 Level 1 (0 points)

    Hmmmm, after now running through all of the steps above, including the short and extended hardware texts (both found no problems) and reinstalling snow leopard, my computer is stlll crashing.


    Advice of what to do now gratefully accepted! 


    Thanks in advance

  • inandoutofgrace Level 3 Level 3 (520 points)

    Some more suggestions:


    1. If you haven't already, back up your HD as soon as possible.

    2. Try creating a new user account and using it to surf the web, etc. Each user account relies on thousands of small files to run properly and it's not uncommon for one to become corrupted.

    3. Boot from the System DVD that came with your computer (instructions are on the disc label) and then use Disk Utility to check and repair your HD.

  • seventy one Level 6 Level 6 (12,060 points)

    Agreeing with all RCR has said I am just wondering if running the 10.6.8 combo update v1.1might help and would just point out that the memory of 2GB is barely sufficient despite what Apple says.   We don't know how much is running in the background.

  • gswg1968 Level 1 Level 1 (0 points)

    Maybe resetting the PRAM could help.


  • nomadic.lucy Level 1 Level 1 (0 points)

    Thanks all for the suggestions!


    @ inandoutofgrace - I have  backed up the HD, will create a new user account and work on that tomorrow and see if there's any difference.  On the Disk Utility suggestion, I've done this already, as did  the Genius Bar, accessing it through Disk Utility directly from Finder.  Will running it from the System DVD be any different?


    @ seventyone - I don't think there's much running in the background.  I'm usually not doing anything other than running Firefox and Word.  When I check on Activity Monitor, it shows low usage (often 98% idle under CPU) and that 1.18GB of my 2 GB system memory is free.


    @gswg1968 - Have just reset the PRAM so will see if that helps.


    If there's any further info that would be useful, feel free to let me know.  I'll see tomorrow how the different user account and PRAM reset work out.  Thanks for all the help

  • inandoutofgrace Level 3 Level 3 (520 points)

    "Will running it from the System DVD be any different?"


    Ordinarily, running Disk Utility from the Finder (i.e. using the copy of Disk Utility that is installed on the HD the computer is booted from) allows verifying, but not repairing, the HD.


    Running Disk Utility from the System DVD will allow Disk Uitility to do repairs on the HD.

  • nomadic.lucy Level 1 Level 1 (0 points)

    Okay - will try that too then.  Thanks for the explanation.