Uh oh...black screen on new late 2015 iMac

Discussion in 'iMac' started by JohnSFO, Nov 8, 2015.

  1. JohnSFO macrumors regular

    JohnSFO

    Joined:
    Jun 10, 2010
    #1
    Was switching between users on my brand new Late 2015 5k retina iMac and the screen went to black. Nothing but a hard restart would bring the machine back to life. A long press on the back button shut it down, so I know it was still on. Another long press brought up the Apple logo and the start-up chime. That was about 4 hours ago and the black screen hasn't returned...yet. I fear if it's happened once it's just a matter of time before it happens again.

    An online search for the problem brought up loads of similar experiences for past iMacs, but I haven't been able to find anyone else reporting this for the late 2015 iMacs.

    I have a Retina 5K, 27-inch, Late 2015; 3.3 GHz Intel Core i5; 16 GB 1867 MHz DDR3 (8GB bought from Crucial); AMD Radeon R9 M395 2048 MB; running El Capitan 10.11.1.

    I've never seen so many ideas out there about fixing the problem. It runs the gamut from wipe hard drive; reinstall software; get a new video card; unplug everything and plug it in again; try a different keyboard; unplug Time Machine; reset PRAM; remove new RAM, and many many more. I'm not ready to do anything until it happens again, but just wondering if it's happened to anyone else with a late '15 iMac.

    Thanks!

    P.S. And of course it happened on day 15 of ownership, so an easy return probably not in the cards. :rolleyes:
     
  2. whodatrr macrumors 6502a

    whodatrr

    Joined:
    Jan 12, 2004
    #2
    Was it a black screen that still had a cursor?

    Happened repeatedly with my new 5k, but within the return period. Ultimately, I wound up returning it on the advice of Apple. But mine may have been different than yours, as it sounded more severe.
     
  3. DeltaMac macrumors 604

    DeltaMac

    Joined:
    Jul 30, 2003
    Location:
    Delaware
    #3
    You could try running the built-in diagnostics test.
    Restart, while holding the D key.
    Run the test.
    Check for errors when the test completes.
     
  4. JohnSFO thread starter macrumors regular

    JohnSFO

    Joined:
    Jun 10, 2010
    #4
    I had read about the black screen with cursor from others' experiences, but I honestly don't remember seeing the cursor when I tried to wake my screen. It might have been there, but I didn't notice it before restarting. If it happens again it's one of the things I'll look for, since it could be a key to the problem. Thanks for asking.
     
  5. JohnSFO thread starter macrumors regular

    JohnSFO

    Joined:
    Jun 10, 2010
    #5
    Thank you so much for this suggestion. I had forgotten that Apple had a built-in diagnostic test, which is really quite wonderful to use when you're questioning your hardware. I ran the test and received a "No issues found" message. That's a bit of a relief, but will only go so far if the black screen returns at a later date. Time will tell.
     
  6. rkaufmann87 macrumors 68000

    rkaufmann87

    Joined:
    Dec 17, 2009
    Location:
    Folsom, CA
    #6
    Don't waste your time, you have 90 days of free AppleCare telephone support, call them immediately.
     
  7. JohnSFO thread starter macrumors regular

    JohnSFO

    Joined:
    Jun 10, 2010
    #7
    Very True! I gave them a call today and we basically went through the diagnostic test again and it came back clean a 2nd time. They really didn't have a solution for me, especially for a problem that's only happened once and hasn't returned yet. She suggested it could be a number of things, including a software glitch. I now have a case number in the event I need to contact them again.

    Obviously I'll be on the alert for any black screen occurrences, and will update this thread if anything happens. Plus we'll see if this problem pops up for other new users of the Late 2015 iMac, since so many people are just now getting their machines.
     
  8. Tantris macrumors newbie

    Joined:
    Nov 29, 2015
    Location:
    San Francisco
    #8
    Same here! Retina 5K, 27-inch, Late 2015, 4 GHz Intel Core i7 was running fine for the first two days, then suddenly, while doing nothing special, the screen went black today, except that the cursor was still visible and still responded to the mouse. Only a hard reboot restored the machine to normal. I too did the diagnostic test right afterward [hold D while restarting] and found no problems.
     
  9. twilexia macrumors 6502

    Joined:
    Oct 16, 2015
    #9
    Just curious OP are you on an SSD or fusion drive?
     
  10. Tantris macrumors newbie

    Joined:
    Nov 29, 2015
    Location:
    San Francisco
    #10
    Yes, I have a 3 TB fusion drive and AMD Radeon R9 M395X 4096 MB graphics card. Also, in case it could be the culprit, I should also mention that I have added 16 GB of Crucial brand RAM to Apple's original 8 GB for a total of 24 GB. [To save hundreds of dollars compared to Apple pre-installing it.]

    I had researched the Crucial memory carefully in Amazon reviews and elsewhere, and people who had added it to a Late 2015 iMac like mine had NOT encountered any problems. Still, I suppose I could be unlucky and just have a bad batch. But could this produce a symptom like the black screen with cursor?

    The black screen has not returned as yet---still only a single, mysterious occurrence.

    THANKS FOR ANY HELP getting to the bottom of this. I'm using it as my main machine for mathematical research and writing, and cannot afford to have it go bonkers on me.
     
  11. JohnSFO thread starter macrumors regular

    JohnSFO

    Joined:
    Jun 10, 2010
    #11
    I have the 512 SSD on my machine. It has now been 3 weeks since I posted the black screen incident and it hasn't happened again, so hoping it was an isolated incident. Tantris, one thing we have in common is the added Crucial brand RAM. I added two 4GB sticks for a total of 16GB. If the RAM is bad or somehow the culprit I feel like we'd have more issues than one blackout.
     
  12. Tantris macrumors newbie

    Joined:
    Nov 29, 2015
    Location:
    San Francisco
    #12
    Agreed: I once installed bad RAM in an old machine, and it crashed constantly, so I DOUBT that could be the problem now, but I'm no computer expert, which is why I was hoping someone on this forum might be able to shed some light on these rare black screens. NOTE: Still no recurrence of the black screen for me. I'm cautiously optimistic, given that JohnSFO himself has now gone three weeks without another occurrence of the black screen. But I don't like mysteries!
     
  13. Gmaster macrumors member

    Joined:
    Nov 8, 2005
    Location:
    Florida
    #13
    Tantris and JohnSFO, Thanks for the updates (no return problems).
    I've ordered Crucial RAM [DDR3 1866 (PC3-14900)], and I'm hoping for no problems.
     
  14. fob macrumors member

    fob

    Joined:
    Sep 11, 2015
    #14
    I would say it is most likely due to the crucial RAM. Did you get the Crucial Ram that was designated for the late 2015 iMac(released recently)? If not, check crucial's CAS Latency. The late 2015 for the iMac uses CL13 ram. AFAIK there are two or three CL ratings of crucial's sodimm ddr3 1866MHZ ram. Crucial Ballistics Sport CL10, a generic CL13, and the officially supported late 2015 iMac CL13 version. Make sure CL ratings match. Dont mix.
     
  15. twilexia macrumors 6502

    Joined:
    Oct 16, 2015
    #15
    I got the black screen (kernel error) twice on my 3tb fusion drive in one night. I think it was because I had 3 USB Hard drives plugged in, although not sure why that would overload the system.
     
  16. JohnSFO thread starter macrumors regular

    JohnSFO

    Joined:
    Jun 10, 2010
    #16
    Got the CL13, DDR3-1866, and even went with two more 4GB sticks so things would match up nicely. I personally don't think it's the RAM. I'm betting on software glitches with El Capitan and hoping things improve with the next update. My black screen happened while switching users. Sometimes when I switch the cursor doesn't automatically appear in the password box. Also, what used to be a smooth, visually appealing transition between users is now buggy. The screen flickers before presenting the last screen. Sometimes it just switches to the screen saver already going. Weird stuff. I've sent feedback to Apple about it. Seems like once they have everything de-bugged in their OS they're already introducing another CA landmark and we start all over again. :(
     
  17. Tantris, Dec 1, 2015
    Last edited: Dec 1, 2015

    Tantris macrumors newbie

    Joined:
    Nov 29, 2015
    Location:
    San Francisco
    #17
    Thanks, fob, for pointing out the mismatch between the CL13 rating of Apple's original RAM and the C10 rating of the Crucial Ballistix Sport memory I installed. However, several people on Amazon have mixed this CL10 Crucial memory with the existing Apple memory and have reported good results.

    Further evidence that the RAM is likely NOT the culprit is the fact that JohnSFO was smarter than me and installed the correct CL13 RAM, and yet he experienced the original black screen that launched this discussion.

    UPDATE: My mixed-CL machine has still not had another black screen (or any crash of any kind), so I'm keeping my fingers crossed that I can go for weeks at a time without problems, as JohnSFO has done.
     
  18. PhillipJ macrumors newbie

    Joined:
    Apr 11, 2014
    Location:
    Denmark
    #18
    How is your black screen working out?
    My new late 2015 Imac just started yesterday doing it. It does it every time it should go in sleep mode, I just can't wake it unless I do a hard reboot.
    How ever I used airplay yesterday too, and on my tv screen it worked, but my Imac just had black screen.
     
  19. DeltaMac macrumors 604

    DeltaMac

    Joined:
    Jul 30, 2003
    Location:
    Delaware
    #19
    Seeing that others have this problem, too - so call AppleCare. If you are within your return period, then that will be easy. Or, repairs within warranty, too.
     
  20. PhillipJ macrumors newbie

    Joined:
    Apr 11, 2014
    Location:
    Denmark
    #20
    I just talked with someone from Applecare, she told me to install OS X again. It just finished. :) I'll test it so see if it works.
     
  21. Tantris macrumors newbie

    Joined:
    Nov 29, 2015
    Location:
    San Francisco
    #21
    UPDATE: It has now been more than a month since my first and ONLY black screen. I'm naturally delighted that the black screen has not returned, but I continue to monitor this thread for insight into the cause.
     
  22. blurfonz04 macrumors newbie

    blurfonz04

    Joined:
    Jan 3, 2016
    #22
    It is still new... you should simply return it or just call Apple Care?
     
  23. PhillipJ macrumors newbie

    Joined:
    Apr 11, 2014
    Location:
    Denmark
    #23
    It is new.
    I tried:
    Shutdown and remove all cables except the keyboard/mouse. This includes the power cable (most important)



    Press and hold the power button for 5 seconds. This resets the SMC (If your Mac doesn't sleep or wake when expected - Apple Support)



    Reconnect the power cable and press the power button and immediatly hold down the Alt-Cmd-P-R to reset the RRAM. Wait for the startup chime and keep the keys pressed until the second chime is heard.


    I haven't got the black screen yet.
     
  24. WhatAmI macrumors 6502a

    WhatAmI

    Joined:
    Sep 2, 2009
    #24
    I had the same issue and a (non-destructive) re-install of OS X solved it for me
     
  25. PhillipJ macrumors newbie

    Joined:
    Apr 11, 2014
    Location:
    Denmark
    #25

    Okay. I did that, but without any luck. So I did what I mentioned above.
    Thanks :)
     

Share This Page