10 Replies Latest reply: Aug 7, 2012 12:53 PM by Mhdr
Mhdr Level 1 Level 1

Last days I have a problem with my Imac. After a while working on Imac my screen turns on black. Imac itself is still running. After a while (30 minutes) if I try again the screen comes back. And then it starts again. Restart does not help. Does anyone know what this can be or similar experiences. Looks like a Hardware problem, which I do not hope. Imac is almost 1.5 years old.

iMac (27-inch Mid 2010), iOS 5.1
  • davidOUo Level 1 Level 1

    I've been experiencing the same problem on iMac 27 (mid-2011) running Lion for almost 2 months now without any solution from Apple Store technicians. Everytime the screen goes black I have to hit the powe button as to put the computer into sleep mode and wake it with the keyboard for the screen to light up again.


    The first time I took the computer to the store on March 3, the technician said the problem was software-related. He reformated the hard drive and did a clean install of OSX.


    The problem persisted.


    When I returned to the store, they decided to change the screen.


    The problem persisted.


    Last week, they change the motherboard and the video card.


    The problem persists.


    I am taking the computer back to Apple Store tomorrow and will ask for an exchange. The computer is unusable (the screen went black seven times since starting this message).

  • Margherita Gracis Level 1 Level 1

    I have been experiencing a similar issue with my iMac running ios 5.1. If I put the computer in sleeping mode, the screen obviously becomes black, but I can not use the computer anymore until I turn it off and on again. This time iTunes was left open and if I use the remote control I can hear music - so the iMac is working, the screen in not! Anyone can help?

  • X423424X Level 6 Level 6

    Try smc and pram reset.


    This may be a overheat problem.  Make sure the intake and exhaust vents (top and bottom) are clear.


    Add a temperature monitor utility like iStat Pro, iStat Menus, Temperature Monitor, Hardware Monitor, etc. and see if there's a correlation between temperature and black out.

  • Mhdr Level 1 Level 1

    Hi, thank you all for your responses.


    I had also a problem with my virussoftware on the Imac. I have installed virusbarrier x6. This virussoftware was reporting error messages in my imac console about a missing file. Besides that it was expired within 12 days. So I decided to remove this virusbarrier software yesterday morning. And guess what? Since then I don't have any problem with my Imac monitor anymore while the Imac was used a lot since then. Maybe too early to draw this conclusion, but it is a little bit strange. I contacted the support of the supplier of virusbarrier and asked for an explanation, but did not get a reaction until now.

  • X423424X Level 6 Level 6

    Strange.  I could understand something like VB causing crashes or strange behavior but I don't understand why it would affect your display.

  • Mhdr Level 1 Level 1

    It worked well for 1 day, but this evening the problem came back agai n so it looks not to be a VB issue. This evening I did a smc reset and a nvram and pram reset, but it didn't help. I can not believe it is a hw issue, because it worked well for 1 day pefectly. I have also installed Istat and monitored the temperatures of the different components, no strange values noticed.

  • Mhdr Level 1 Level 1

    Now it looks that it is over. After startup (from hard start or from sleep mode) screen comes up for 3 seconds and then it turns on black and remains black. Does someone recognise ths?

  • Chris Lephart Level 1 Level 1

    Di you ever find a solution to this problem I have a iMac in our office doing the same thing. The screen turns on breifly then goes black. I can run it using and external monitor but not really how I want to keep running it.

  • Wapiti95 Level 1 Level 1

    Hi. August 2012. My 21 inch 1 year old iMac is doing this.  I am using two displays, and the external one works just fine, allowing me to do a hardware check. My computer does not recognize its internal monitor. I think it could be a bad video card or connection to or from the video card. At the time, when I felt the exhaust ports, things were hot.


    I am disappointed that no Apple response has been posted, nor has anyone posted a solution related to an Apple repair.


    Has anyone found that a good vacuuming has helped, or anything else?


    If an Apple person is reading this, you might be interested to know that I have been an Apple person since the IIe - while using and creating various DOS and Windws based networks and computers over the years, and that this iMac (which in itself was a replacement for an iMac that died within three weeks of purchase, and that that one was a replacement for an iMac that was dead right out of the box), is the poorest, worst, most disappointing computer that I have ever owned.  I am pretty sure that my next purchase, likely within weeks since my iMac is broken once again, will be a Windows-based PC and not another Apple product.


    My home network is totally Mac, I was going to buy an Apple TV, I have one of the last Motorola laptops, and old Mac Mini, and up u til this machine generation have recommended Apple products. No longer.


    Same for my phone, and my next tablet.


    I am totally fed up with the lack of solution posted by Apple for this problem.

  • Mhdr Level 1 Level 1

    Hi all,


    At the end my turned black and did not come back. my problem was solved by replacing the display.


    Thanks you all for your help.