NodScene

Q: iMac white screen of death

Hi everybody,

 

Since I have had this problem for a while now and searched forums online extensively I am positive that my issue has not been resolved in any other thread I know of. I hope that someone here might be able to help me. I have iMac 27 inch from 2011 (EMC2429) running El Capitan suffering from white screen of death.

 

The problems started with chrashes during online video playback. I formatted and made several clean installs of both El Capitan and Snowleopard. From being intermittent the problems are now more consistent. While I at this moment never have problems using the computer if I get it to start, from time to time it will not boot properly even after several attempts of restart. In detail: I start the iMac up; white screen for a short while; the logo comes on and when the progress bar reach about 50 % I get a white screen for a minute or two, then spontaneous restart and we're in a loop. I used to think that this issue was predictable since the problem is persistent when it do start to occur, but I have been fooled a couple of times. Upon turning it in to a genuis bar and had it checked and "cleaned" it worked for a while but the problem was not remedied. A while after that I recently changed the hard drive and I thought the problem was finally solved, until today. As I am writing this post while trouble shooting to give you the latest symptoms, the computer finally made a successful boot. Most of the times (as I now have to phrase it) I cannot boot into safe mode - before I could and it momentarily fixed the problem - now I cannot finish internet recovery or boot from an external drive. I can start in verbose mode as well as single user mode every time though. That's maybe the only thing I can say for certain as the issue keeps changing, which also makes it so difficult to describe.

 

I have tried to boot without RAM as well as checking the RAM one by one and one time when the iMac is acting up and won't boot properly after several tries. While changing the hard drive I discovered that the computer was quite dusty on the inside. I will buy some compressed air an try to clean it. After that I am out of options. I guess there might be an issue with the logic board but I got the 5 (?) beeps without the RAM installed. That leaves us (at least to my knowledge) with the GPU. This model is infamous for it's potential issues with the graphics card (I should know the brand and model of it but I have not written it down and google gives me several different answers) but I have not experienced glitches and artifacts like other users have and GPU does not seem to act up when I put it under stress. I have seen black and white stripes over the screen upon booting the last time the computer had a fit.

 

I am determined to try and fix this computer myself - partly because I have no money to send it to a repair shop and partly because I like the challenge (at the moment) - and any tips are highly appreciated.

Posted on Sep 22, 2016 12:15 PM

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Q: iMac white screen of death

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  • Helpful answers

  • by rkaufmann87,

    rkaufmann87 rkaufmann87 Sep 22, 2016 12:18 PM in response to NodScene
    Level 9 (58,746 points)
    Photos for Mac
    Sep 22, 2016 12:18 PM in response to NodScene

    Please create an EtreCheck report of your system. We can then look for obvious issues. Please click the link, download the app and run the report. Once you have the report, please copy and paste it to your reply to this post.

     

    If you would like more info on what EtreCheck is, simply click the link and you will find a description of the app.

  • by NodScene,

    NodScene NodScene Sep 22, 2016 2:07 PM in response to rkaufmann87
    Level 1 (8 points)
    Desktops
    Sep 22, 2016 2:07 PM in response to rkaufmann87

    Hardware Information: ⓘ

        iMac (27-inch, Mid 2011)

        [Technical Specifications] - [User Guide] - [Warranty & Service]

        iMac - model: iMac12,2

        1 3,1 GHz Intel Core i5 CPU: 4-core

        12 GB RAM Upgradeable - [Instructions]

            BANK 0/DIMM0

                2 GB DDR3 1333 MHz ok

            BANK 1/DIMM0

                2 GB DDR3 1333 MHz ok

            BANK 0/DIMM1

                4 GB DDR3 1333 MHz ok

            BANK 1/DIMM1

                4 GB DDR3 1333 MHz ok

        Bluetooth: Old - Handoff/Airdrop2 not supported

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

     

    Video Information: ⓘ

        AMD Radeon HD 6970M - VRAM: 1024 MB

            iMac 2560 x 1440

     

    System Software: ⓘ

        OS X El Capitan 10.11.6 (15G31) - Time since boot: about 2 hours

     

    Disk Information: ⓘ

        WDC WD3200AAJS-00VWA0 disk0 : (320,07 GB) (Rotational)

            EFI (disk0s1) <not mounted> : 210 MB

            BareKnuckles (disk0s2) / : 319.21 GB (275.34 GB free)

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

     

        HL-DT-STDVDRW  GA32N   ()

     

    USB Information: ⓘ

        Apple Inc. FaceTime HD Camera (Built-in)

        Apple Inc. BRCM2046 Hub

            Apple Inc. Bluetooth USB Host Controller

        Apple Computer, Inc. IR Receiver

        Apple Card Reader

     

    Thunderbolt Information: ⓘ

        Apple Inc. thunderbolt_bus

     

    Gatekeeper: ⓘ

        Mac App Store and identified developers

     

    Kernel Extensions: ⓘ

            /Library/Extensions

        [loaded]    at.obdev.nke.LittleSnitch (3.6 - SDK 10.8 - 2016-09-20) [Support]

     

            /System/Library/Extensions

        [not loaded]    com.focusrite.driver.usb.audio (3.0 - SDK 10.11 - 2016-09-20) [Support]

     

    System Launch Agents: ⓘ

        [not loaded]    8 Apple tasks

        [loaded]    151 Apple tasks

        [running]    79 Apple tasks

     

    System Launch Daemons: ⓘ

        [not loaded]    47 Apple tasks

        [loaded]    156 Apple tasks

        [running]    87 Apple tasks

     

    Launch Agents: ⓘ

        [running]    at.obdev.LittleSnitchUIAgent.plist (2016-09-20) [Support]

        [not loaded]    com.adobe.AAM.Updater-1.0.plist (2016-09-20) [Support]

     

    Launch Daemons: ⓘ

        [running]    at.obdev.littlesnitchd.plist (2016-09-20) [Support]

        [loaded]    com.adobe.SwitchBoard.plist (2016-09-20) [Support]

        [loaded]    com.adobe.fpsaud.plist (2016-08-30) [Support]

        [running]    net.exirion.ssdfanctrl.plist (2013-10-31) [Support]

     

    User Launch Agents: ⓘ

        [loaded]    com.bittorrent.uTorrent.plist (2016-09-19)

        [loaded]    com.pia.pia_manager.plist (2016-09-19)

     

    User Login Items: ⓘ

        SSD Fan Control    Application  (/Applications/SSD Fan Control.app)

        smcFanControl    Application  (/Applications/smcFanControl.app)

     

    Internet Plug-ins: ⓘ

        FlashPlayer-10.6: 23.0.0.162 - SDK 10.9 (2016-09-21) [Support]

        QuickTime Plugin: 7.7.3 (2016-07-09)

        Flash Player: 23.0.0.162 - SDK 10.9 (2016-09-21) [Support]

        Default Browser: 601 - SDK 10.11 (2016-07-09)

     

    3rd Party Preference Panes: ⓘ

        Flash Player (2016-08-30) [Support]

     

    Time Machine: ⓘ

        Time Machine not configured!

     

    Top Processes by CPU: ⓘ

             9%    mdworker(13)

             2%    WindowServer

             1%    fontd

             1%    kernel_task

             1%    ocspd

     

    Top Processes by Memory: ⓘ

        842 MB    kernel_task

        553 MB    mdworker(13)

        430 MB    firefox

        283 MB    plugin-container

        160 MB    Mail

     

    Virtual Memory Information: ⓘ

        4.59 GB    Free RAM

        7.41 GB    Used RAM (2.82 GB Cached)

        0 B    Swap Used

     

    Diagnostics Information: ⓘ

        Sep 22, 2016, 08:36:23 PM    Self test - passed

  • by NodScene,

    NodScene NodScene Sep 22, 2016 2:11 PM in response to rkaufmann87
    Level 1 (8 points)
    Desktops
    Sep 22, 2016 2:11 PM in response to rkaufmann87

    I may have accidentally reset the SMC a couple of times when I've given up on and unplugged it or that time when I turned it in. That might have made the problem go away (I did try it at one time but it did not help so I didn't bother thinking about it). Something tells me there are several unrelated issues. SMC might be one thing. I'll trouble shoot it next time I get the chance.

  • by rkaufmann87,

    rkaufmann87 rkaufmann87 Sep 22, 2016 2:26 PM in response to NodScene
    Level 9 (58,746 points)
    Photos for Mac
    Sep 22, 2016 2:26 PM in response to NodScene

    I suspect the GPU is failing but that is just a guess as nothing shows up on the report and your machine has the GPU and symptoms that was affected in the iMac (27-inch): AMD Radeon 6970M Video Card Replacement Program - Apple Support. That program has ended so you cannot take advantage of it. Any replacement would be an out-of-pocket expense.

     

    Good luck.