iMac Sleep Problem Waking - Screen Black & Pixelization

Discussion in 'iMac' started by gswilder, Dec 21, 2011.

  1. gswilder macrumors regular

    Oct 3, 2007
    Have a new BTO 27" iMac I received a couple of weeks ago. Of course it is running Lion 10.7....

    I am having a screen problem "waking" my iMac. (I also have this problem randomly on my MB Air - mid 2011 model)

    After the iMac is in true sleep mode
    (I have it set to enter a password after sleep mode)
    Screen is blank/off
    I "wiggle" my mouse or trackpad
    Screen is still blank (sometimes it may display my screen saver, but the screensaver is frozen)
    If I start moving the mouse or trackpad, it starts "un painting" the black screen. You can see whatever is supposed to be on the screen, such as the logon "button".
    It is really wierd. Like a black "overlay" is painted on the resume from sleep screen. As I move my mouse or trackpad, it is basically erasing the black, to show what is underneath. Each movement of the mouse, erases a small black square.
    I usually move my mouse around the middle of the screen to uncover the logon button. Press the logon button. The screen magically reappears as normal. I enter my password and system logs back on normally.

    It only seems to be when the iMac is in really deep sleep mode. If the screen is just blank for an hour or so. I move the mouse/trackpad, and the logon screen is immediately displayed normally.

    Any thoughts or recommendations?
    Thanks to all in advance.
  2. gswilder thread starter macrumors regular

    Oct 3, 2007

    Still experimenting.

    If certain programs are running (ie Firefox), then I don't have a problem coming out of deep sleep. It gives me a message when I reenter my password, that Firefox prevented the system from logging off.

    Does that additional information help? It is a really annoying problem. And since I have it on my MBA, I am concerned it is more widespread. Does anyone else have this issue?
  3. UNCHeelYeah macrumors newbie

    Dec 24, 2011
    Black Screen and "Erasure" with Mouse.

    I am having this same problem. I am using the Mac OS X Lion 10.7.2, not using a screen saver, and it happens sporadically upon trying to wake my iMac from sleep mode. The screen is black, and as you move the mouse over the screen, it "erases" the black, like the opposite of a blackboard, to reveal the login name and picture underneath. After that everything works fine. There is no pattern to this that I can discern (e.g. - happens every fifth time, only happens when a program isn't running etc.). It appears random, but is uber annoying, and behaves like a virus. I have Norton Antivirus, and it updates daily, and upon scanning states no virus is found. I also do system scan with MacKeeper, and it scans, says system is excellent. Something is definitely going on, I just wish I knew what it was. If anyone has any knowledge of this, any solution or insight would be greatly appreciated! Thanks!
  4. GGJstudios macrumors Westmere


    May 16, 2008
    That's because there are no Mac OS X viruses. You should uninstall Norton. You don't need 3rd party antivirus apps to protect your Mac from malware. Macs are not immune to malware, but no true viruses exist in the wild that can run on Mac OS X, and there never have been any since it was released 10 years ago. The only malware in the wild that can affect Mac OS X is a handful of trojans, which can be easily avoided with some basic education, common sense and care in what software you install. Also, Mac OS X Snow Leopard and Lion have anti-malware protection built in, further reducing the need for 3rd party antivirus apps.
    You don't need MacKeeper, either. You really don't need "cleaner" or "maintenance" apps to keep your Mac running well, and some of these apps can do more harm than good. Most only remove files/folders or unused languages or architectures, which does nothing more than free up some drive space. It will not make your Mac run faster or more efficiently, since having stuff stored on a drive does not impact performance, unless you're running out of drive space.

    Mac OS X does a good job of taking care of itself, without the need for 3rd party software.

    Your problem, and the OP's is a graphics problem, likely having to do with the screensaver, not a malware problem.
  5. UNCHeelYeah macrumors newbie

    Dec 24, 2011
    Norton Antivirus, and what does it mean?

    I suppose one reason I developed a concern that there was more here than meets the proverbial eye, so to speak was a message that I have received through Norton on multiple occasions. The last message of similar stated messages reads as follows (Norton Antivirus 2.2.1 (5) ): "Vulnerability blocked, December 13th, 2011, 8:57 P.M. When I click on "View Recent Activities", a window is opened that is titled "Activity Log." There, four columns are listed, titled from left to right "Date", "Event Type", "Result", and "Details." Under the December 13th episode, It lists "Portscan" under Event type, "Result" gives an IP Address (, and "Incoming" under details.

    I am admittedly a neophyte in the Mac world, having switched over from Windows 7 to Mac recently, but am intent on educating myself to the not-so-subtle differences. The above information that Norton displayed would lead one to believe that their antivirus software is protecting my iMac, and that its subsequent removal would have perhaps disastrous results ( i.e. - my iMac would be susceptible to said "Vulnerability", whatever it is, and that "Incoming would NOT be blocked). I had a conversation with Norton because previously, every time the stated "Vulnerability" attempted access, I was interrupted by a pop-up screen informing me of this. The Norton representative was able to turn off the pop-up screen notification, but stated that it would continue to log episodes of the "Vulnerability" when it attempted to portscan and access. So am I to understand that uninstalling Norton would leave my computer no less vulnerable to this vulnerability? It is confusing to me.

    Furthermore, I suppose I did wonder if this vulnerability threat had anything to do with the issue of the black screen erasure with the mouse. I will attempt to post a picture of the screen as it was being erased with the mouse, and perhaps a short movie as well. As previously stated, I do not have a screen saver enabled. Thank you for your input, any information is helpful to me! _

    Attached Files:

  6. gswilder thread starter macrumors regular

    Oct 3, 2007
    Ditto & FYI Workaround


    Thanks for posting the picture. It is same as my iMac problem. On my iMac, it happens 100% of the time. On my MBA, it happens randomly like yours.

    I began to notice if certain programs were running, when it went into screen saver and sleep mode, this didn't happen. And when I woke it up, I got a message that said "could not be logged off due to Firefox or Sketchbook Pro, etc. So that got me to thinking. So....

    Over the weekend, I disabled "logoff after xx minutes of activity" in system preferences. That seems to fix the issue. I still have it set to require a password after the screen saver/sleep mode kicks it. But I disabled the logoff toggle.

    Still not sure what this is an issue, but seems to be a work around. I just want to make sure my iMac is still going into sleep with these new settings. Including the monitor sleep.

    Any thoughts based on this new information?
    Thanks again
  7. GGJstudios macrumors Westmere


    May 16, 2008
    You have to remember that many antivirus apps consider cookies to be a "vulnerability" or "threat", when they're not. The only malware in the wild that can affect Mac OS X requires the user to actively install it. As long as a user is reasonably careful about where they get software, there is no need for 3rd party antivirus apps to protect Mac OS X from malware. Just make sure your firewall is enabled (System Preferences > Security > Firewall), and disable Java in your browser (Safari > Preferences > Security > Enable Java (uncheck))
    You can let it sleep without logging off. That way, your apps/documents are still open when you wake it up, rather than having to relaunch apps and reopen documents. Recovery from sleep is much faster than from logging off.
  8. rda2w macrumors newbie

    Oct 16, 2011
    I have had the same problem on my mid-2010 iMac since upgrading to Lion and it's been driving me nuts. The relation to automatic Logoff makes sense to me now that I look at my settings. The logoff was occurring after sleep and it's the only thing I haven't tried yet. I had previously thought it was related to Sleep but it never occurs if I force it to sleep. It only occurs after the system was left unattended and went through it's normal steps of screensaver then sleep. I'll try disabling the automatic Logoff and see if it fixes the problem for me too.

  9. rda2w macrumors newbie

    Oct 16, 2011
    I can only declare partial success with unpicking "logoff after xx". It solved the pixelated screen issue but now the computer is not sleeping. I guess I'll have to uncheck file sharing now.
  10. ougrad1764 macrumors newbie

    Apr 6, 2010
    Any updates?

    Just wanted to see if there had been any changes since the last posting in this thread. I'm experiencing the same issue as OP on my 2011 13" MacBook Air w/ OS X 10.7.3, as well as on my parents' mid-2010 iMac (running OS X 10.7.2).

    I can't seem to pin down the cause and have tried the steps suggested previously. Thanks!
  11. wchp, Feb 21, 2012
    Last edited by a moderator: Feb 21, 2012

    wchp macrumors newbie

    Feb 21, 2012
    Still having the same issue here as well.

    Have any of you tried a clean install of OSX?
    Before I try a full reinstall I did an install on a external drive with no aps, just the bare install and I could not replicate the issue.
    I continue to question if this is a graphics card firmware issue or and OS issue.
    A reinstall (overlay) of the OS did not resolve the issue.
    I have screen shots as follows:
    1) Paint pixels on screen
    2) Click Icon
    3) Type in PWD
    4) Logged in:
  12. jrobin macrumors newbie

    Feb 21, 2012
    Having the same issue

    I have four MacBooks and a MacBook Air. I am seeing this issue on two MacBooks both running Lion 10.7.3. One is a newer i5 MacBook the other is an early 2010. The only common denominator I can think of is they are both set up with Parental Controls and they are set to logoff after X amount of time. The other MacBooks don't have this "pixel painting to revel the login screen issue" I also don't see it on our iMacs or the MacMini. Only the two with the issue are set to auto logoff. So the above poster is most likely on to something. I will give it a try by turning off the auto logoff on the two MacBooks in question. If that solves the problem then I will assume its a bug that needs to be addressed.
  13. ougrad1764, Feb 21, 2012
    Last edited: Feb 21, 2012

    ougrad1764 macrumors newbie

    Apr 6, 2010
    reinstall (overlay) of the OS did not resolve the issue

    wchp - Thank you for following up and posting the screenshots. They match exactly what I was experiencing (and what UNCHeelYeah reported previously). I can confirm that I experienced the issue even following a clean reinstall of Snow Leopard on my MacBook Air (13-inch, Mid 2011).

    jrobin - "I will give it a try by turning off the auto logoff on the two MacBooks in question. If that solves the problem then I will assume its a bug that needs to be addressed."

    Good thinking! Thanks for taking the time to test with your machines. This will help provide further validation of what gswilder (OP) tried as well in reply #6. Interesting about Parental Controls, too.

    Side note:

    Since I recently joined the Apple Developers program, I did a clean install of SL on my MBA then upgraded via the App Store to Mountain Lion to "kick-the-tires" if you will. Interestingly, I've not yet experienced any issue related to waking from sleep with a black screen and pixilation, even while running all the same apps I had previously. I'll report here (and file a bug report with Apple) if I do see this issue pop-up in ML. I'll be reinstalling SL in a few weeks and will report back if/when the black screen and pixelation issue reappears. I'll be sure to note the applications left running at the time the computer went to sleep.
  14. evillanueva macrumors newbie

    Feb 22, 2012
    I have experienced the same issue with my brand new MBA Late 2011.

    I recently found out that this only happens when DISPLAY is set to go to sleep minutes before the "Log out after X minutes of inactivity". I had "Display sleep" option set to 5 minutes and "Log out after 10 minutes of inactivity" and this causes the display to go to sleep first (screen goes black) and then, 5 minutes later, it logs out.

    If "Display sleep" is off and "Log out after X minutes of inactivity" is on, the issue does not replicate. So Im thinking it has something to do with the screen being black at the moment it logs out. Can you try and replicate that?

  15. wchp macrumors newbie

    Feb 21, 2012
    Just tested this premise and yes, you are correct.

    IF: Screen saver ON after 5m AND require password immediately AND Sleep (Display) after 30m AND Logout after 60m I am able to reproduce the problem.

    IF: Screen Saver ON after 5m AND require password immediately AND Sleep (Display) after 30m AND Logut after xx NOT enabled, problem goes away

    IF: Screen Saver ON after 5m AND require password immediately AND Sleep (Display) OFF AND Logut after 60M enabled, problem goes away

    So on my machine (iMac 27, 3.4/i7, 16GB/1333, Radeon 6970m/2048MB, OSX 10.7.3

    It would appear that if I am running Monitor Sleep and it kicks in prior to LogOff then I am able to reproduce this artifact. Only Display sleep with immediate login OR Loguot should be used but not both.
    The only other thing to test is is I leave display sleep on, and screen saver on but with NO immediate password and enable logoff if the problem goes away.
    Testing for another day.
    I have linked this entire thread to a Apple support ticket and will report back on Apples response
  16. Emmasyd macrumors newbie

    Feb 26, 2012
    Hello. I also have this problem on a MacBook Air I bought in Sept. 2011. I have phoned Apple support on numerous occasions - they essentially do not seem to have a clue. I do not live near an Apple store so over the phone I have done all the possible resets, PRAM etc, reinstalled the operating system and finally wiped the hard drive and reinstalled the operating system. None of which helped with the sleep/pixel issue.

    I finally took the Air into a store, where they tested the hardware over 48 hours and found nothing wrong. Again they suggested wiping the hard drive and reinstalling the OS. This did nothing to help. Following this I telephoned Apple support again and finally spoke to an adviser who, having read the case notes, said that he had encountered the problem a couple of times previously and he believed it to be a clash between the option Log out of .... minutes of inactivity under Security and Privacy and Computer Sleep in Energy Saving. He said that if the length of time selected to Log out, say 15 minutes, was greater than the time selected for Computer Sleep, say 10 minutes, this would lead to a clash.

    His solution was to leave the Log out box unchecked to ensure that the issue would no longer arise. Since this conversation I no longer have this particular problem. However, I don't consider it to be a solution as there may come a point when I do need to log out... however it works for now.

    I am still experiencing a problem with my sleep and screensaver - in that when I close the lid of my Air with the screensaver running, upon waking the screen displays a frozen image of whatever picture was on the display when the lid was closed. It will freeze for about five seconds before flashing to a black screen with my password login. It is as if the computer freezes on a particular image and does not sleep properly.

    So while, unselecting the log out option has resolved one part of my problem, it has not completely resolved the sleep issue and I will be calling Apple again tomorrow for further help.
  17. wchp macrumors newbie

    Feb 21, 2012
    Apple acknowledges issue

    Spoke with the Sr. technician to whom my original case was escalated to last November. Apple acknowledges the issue (logout) and it is on the bug list. There was no eta on resolution but the workaround was to either use your screen saver OR logout and make sure the display sleep was set to a time period greater than the logout or screensaver time.

    My personal feeling on this is that the use of auto-logout is problematic in general so I have simply stopped using it until apple addresses the issue.
  18. wchp, Feb 26, 2012
    Last edited: Feb 26, 2012

    wchp macrumors newbie

    Feb 21, 2012
    Please don't perpetuate the "security by obscurity" model.

    "This new variant of the Flashback Trojan horse uses three methods to infect Macs. The malware first tries to install itself using one of two Java vulnerabilities. If this is successful, users will be infected with no intervention."


    Please everyone... don't perpetuate the "security by obscurity" model. Macs are not impervious to viruses or malware. Just because we haven't been a target does not mean we are immune. Most modern attack vectors are social engineering based and or backed up by OS or application vulnerabilities .

    How many OSX users even have passwords on their systems?
    I even have been asked by genius bar staff why I use a password!:eek:
  19. GGJstudios macrumors Westmere


    May 16, 2008
    Did you even take the time to read my post that you quoted? Apparently not.
    Most, as selecting a password is part of the initial setup process.
    It's important to remember than "Genius" is only their job title, and not necessarily an indication of their knowledge, experience or expertise. They are frequently wrong.
  20. wchp macrumors newbie

    Feb 21, 2012
    Our company supports Hospitals, Medical practices, Legal offices and Insurance companies. Over 90% of our users are PC/Windows based. As of this year OSX and IOS now comprise almost 10% of our supported user base. Caution and common sense are not part of the mix in most enterprise IT environments.
    I did read your post thoroughly and I agree with most of your comments and only take note with you saying an AV package is not needed. ALWAYS protect against the lowest common denominator. The particular trojan article I linked too uses a self signed cert that most users will not know what to make of. This trojan infected a total of 28 hosts across all of our customer base. Fortunately it infected personal (privately owned machines) which were not under our management and were caught when brought in and connected with the corporate environment. Of the 28 OSX hosts only 5 of them had password protected accounts. The rest(passwords) had been disabled by the end users.
    Most of the folks that will post here are more astute but for the general population to suggest that common sense, caution and care will avail them of infection is just not what happens in the real world.
    I suggest/recommend that every mac user download and install the a/v package (paid or unpaid) of there choice and install and run it. The more popular OSX and IOS based hosts become the more they will be targeted by malware and viruses.
    I apologize in advance to others on this thread that the image issue was temporarily hijacked by GGJstudios and my discussion of AV on OSX.
    GGJstudios, please feel free to start another thread in AV or IM me and I would be more than willing got continue this discussion. I just disagree with your suggestion that AV in general is not needed and common sense and caution will prevail. I have seen this stance fail on multiple occasions in the real world.
    Would you want a doctor with no IT background using his mac to enter Personal Health Information about you and the host NOT have AV and other security measures? I am a plan for the worst and hope for the best IT person. I don't believe in taking chances with anyones information or privacy!
  21. GGJstudios macrumors Westmere


    May 16, 2008
    There's the source of your problems. Common sense, a bit of education and reasonable care will protect a Mac user better than any antivirus app. If someone wants to run AV, that's their choice, but IF they exercise some reasonable care, it's not necessary. For evidence of this, look back at the case of the MacDefender trojan, which no antivirus app was able to detect when it was first introduced, yet was easily avoided by any user who had enough common sense not to be "duped" by it.
  22. wchp macrumors newbie

    Feb 21, 2012
    You made me think of a totally politically incorrect video:
  23. GGJstudios macrumors Westmere


    May 16, 2008
    I'm not interested in watching any video, but there's nothing I said that is politically incorrect... or incorrect in any other way.
  24. NJCathie macrumors newbie

    Aug 12, 2010
    Thank you everyone this was driving me INSANE

    I'm not a Mac pro by any means, but after I updated my iMac to Lion I am having this EXACT issue! It's good to know it's a bug, but bad to know Apple only sees it as a "future' bug fix and we are three months of having this problem - at least on this thread.

    Because I'm a MAC newbie I didn't even think I could explain it and was stuck with moving my mouse back and forth over the middle of my screen until I found the login box.

    But I have one added issue to this, once I login after the sleep mode it makes every application that has a blue dot under it open to full screen once it wakes up. iTunes, my Dashboard include calc, my mail and others and I have to close each one individually every time it comes out of sleep mode.....very annoying and tedious "x"ing them all down each time.

    I keep my iMac on so it does go into sleep mode on many occasions, so the sooner they roll out a fix the happier I'll be!

    Thanks again for helping clear up my insanity.
  25. getrusty macrumors newbie

    Dec 30, 2008
    iMac OSX 27" i5 - Same issue

    I have been experiencing the same issue on my 27" iMac 2.7GHZ i5.

    I get the archiving when waking up the mac with mouse movement. My screen typically is divided into 4 quadrants 3 of which start out black and you can see the login password box in the center.

    If the bug fix is in the cue it would nice to resolve this since I have not had this issue prior to this new iMac I picked up in dec 2011.

    Apple team please fix this.


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