iMac 2011 very mild flickering after SSD and RAM upgrade

Discussion in 'iMac' started by InfoTime, Mar 4, 2015.

  1. InfoTime macrumors 6502

    Joined:
    Jul 17, 2002
    #1
    Just upgraded machine by replacing internal hard drive with an SSD and added more memory. Everything works great except there's a very minor, mild flickering of the screen.

    The whole screen flashes. It's almost imperceptible. And it doesn't do it consistently or predictably. Sometimes I'll look over at it and think it's gone away, but if I stare at it long enough I'll see it.

    I may have damaged the display cable when I opened the machine. As I was carefully lifting up the display and removed or removing the vertical sync cable the display data cable popped loose.

    I also may have bent the cable by flexing it too much when putting it all back together. It was difficult getting that connector seated. It's not damaged, but it's just in a difficult spot.

    The symptoms lead me to suspect a problem with the backlighting. But I wonder if it's the display data cable, since I'm afraid I might have damaged something - either the connections or kinked the cable..

    I've gone back in to the machine and disconnected and re-seated all three cables - the vertical sync, the data display and the LED backlight power cables. The issue persists.

    Any suggestions?
     
  2. vkd macrumors 6502a

    vkd

    Joined:
    Sep 10, 2012
  3. RichMilo macrumors newbie

    Joined:
    May 31, 2013
    #3
    Like an old TV set, just give it a hard slap on the side til the picture is good ;)

    In seriousness tho I just had the same problem upgrading my brothers Mac, and am going to look at it tonight. I'll let you know if we get it sorted out.

    Rich
     
  4. InfoTime thread starter macrumors 6502

    Joined:
    Jul 17, 2002
    #4
    Be interested to see what you find. I ordered a new display data cable. Hopefully that's all that it is. I may have damaged the connector and / or kinked the cable to cause this.
     
  5. strukt macrumors member

    strukt

    Joined:
    Aug 8, 2012
    Location:
    Norway
    #5
    The connector is very fragile so you should be aware of that when working inside the iMac. Also make sure you flip the locking lever up... thats pretty important too.

    Lets hope its just the cable though, crossing fingers! ;)

    If all cables are okay and you still get flickering it could be the backlight/inverter board on top left.
     
  6. InfoTime thread starter macrumors 6502

    Joined:
    Jul 17, 2002
  7. Dopeyman macrumors 6502a

    Joined:
    Sep 5, 2005
    Location:
    Los Angeles!
    #7
    If it's a 27" iMac, take it to the Apple Store to get it checked out...

    My iMac fell culprit to the video card failing and it was replaced free of charge within a week...
     
  8. InfoTime thread starter macrumors 6502

    Joined:
    Jul 17, 2002
    #8
    Were you outside the warranty period? What model year iMac? Is it a well documented recall?
     
  9. kepler20b macrumors 6502

    Joined:
    Oct 18, 2014
    #9
    you should be sure that your cables are seated properly.

    I'd open it back up and reseat them. Also i'd remove the new ram and try to pinpoint the issue.
     
  10. Dopeyman macrumors 6502a

    Joined:
    Sep 5, 2005
    Location:
    Los Angeles!
    #10
    I left the link where it says "Apple Store".... It's for a 2011 27" iMac.... Yes... It's a well documented recall..... :)
     
  11. Walde macrumors newbie

    Walde

    Joined:
    Jan 3, 2016
    #11
    a bit late, but for those who have the same problem:

    There are 4 cables. When the screen is light flickering, you have forgotten to reconnect the thin cable with the two pins on the upper left side (for the imac 21.5 middle 2011)

    sorry for the bad english....
     
  12. Walde macrumors newbie

    Walde

    Joined:
    Jan 3, 2016
    #12
    a bit late, but for those who have the same problem:

    There are 4 cables. When the screen is light flickering, you have forgotten to reconnect the thin cable with the two pins on the upper left side (for the imac 21.5 middle 2011)

    sorry for the bad english....
     
  13. InfoTime thread starter macrumors 6502

    Joined:
    Jul 17, 2002
    #13
    I installed a new replacement display cable. Problem solved.

    I think the original cable must have gotten crushed or twisted or bent somehow. It wasn't nice and flat like the new one.
     

Share This Page