Please visit the new Mac-Forums Facebook page:
Join Us @ Mac-Forums Facebook Page




Results 1 to 11 of 11
  1. #1
    Thumbs down Late 2015 imac - real dog of a machine - help!
    For most of its life this machine has been a real dog and source of considerable frustration.

    I have to restart this machine each session or nothing happens( dreaded spin-wheel goes interminably or nothing happens). I have had to connect my keyboard and touch pad with cables as the bluetooth crashed all the time.
    painfully slow and locks up regularly ( my 2012 Macbook pro with SSD is streets ahead ). All tests pass and untold re-installations, replacement circuit board, and upgrades achieve nothing.Geekbench scores for multicore is a 98% and single core is 92% of average for the device, which doesn't appear too problematic.

    Often I can't even activate Command /Shift/Escape and have to resort to holding down the on/off button to crash the machine( Probably daily) just to keep going.

    Now,unfortunately, I upgraded to Catalina and my screen calibration device ( colormunki smile) is no longer compatible!

    if I replace the machine with another iMac can I have confidence that it is going to perform any better?
    I use the machine mostly for processing and filing RAW photos(on an external USB HD) using Photos with Skylum Luminar, Aurora, and some minor programs as extensions .I am not into massive RAW files ( max about 22 MP) The only thing stopping me throwing away the iMac and going to Windows is the problems it will create with converting my photo files!

    Is it possible to get a Mac Mini and use the iMac only as a monitor, to save the cost of a full replacement?

  2. #2
    Late 2015 imac - real dog of a machine - help!
    ferrarr's Avatar
    Member Since
    May 21, 2012
    Location
    Pawtucket, RI, US
    Posts
    6,855
    Your Mac's Specs
    L2014 Mac mini macOS 15, iPhone 8+ iOS 13, 12.9" iPad Pro 1 iPadOS 13,  Pencil 1
    Rep Power
    13
    If it is a 2015 iMac, it is not useable as a monitor, here's what Apple says, Use your iMac as a display with Target Display Mode - Apple Support, about it.
    -- Bob --
    Please backup. Everything has a life cycle, unexpected and warning free. Nothing will last as long as you want it to.

  3. #3
    Late 2015 imac - real dog of a machine - help!
    pigoo3's Avatar
    Member Since
    May 20, 2008
    Location
    U.S.
    Posts
    41,368
    Your Mac's Specs
    2011 17" MBP 2.2ghz, 16gig ram, OS 10.11.6
    Rep Power
    43
    Quote Originally Posted by Khandakulu View Post
    For most of its life this machine has been a real dog and source of considerable frustration.

    I have to restart this machine each session or nothing happens( dreaded spin-wheel goes interminably or nothing happens).
    Possible area's/things to check are:

    - Possible bad internal drive...especially if it's a "spinner" hard drive.
    - Drive could be full or near full.
    - Drive could use some maintenance.
    - Maybe have some "screwy" 3rd party stuff installed...like anti-virus apps...anti-malware apps...cleaner apps...etc.

    * Nick
    - Too many "beachballs", read this: Beachballs
    - Computer seems slower than it used to? Read this for some slow computer tips: Speedup
    - Almost full hard drive? Some solutions. Out of Space
    - Apple Battery Info. Battery

  4. #4
    1) Possibly although Diagnostic restart and Disc Utility first aid showed nothing ( it did sound a bit scratchy though when the diagnostic spun up the disc)
    2) Drive less than 25 % full
    3) See 1 above
    4) I think the machine is pretty clean with only free AVG antivirus, some Skylum photo editing software, GIMP, Firefox , some Adobe bits, Google bits, Flip4Mac, Whatsap, Canon printer utilities, Trash it (if all else fails) Skype, Android file exchange, and that is about it, in addition to the usual MAC suite.

    I believe the motherboard was replaced about 9 months ago, but with no effect.Unfortunately the periods when the system works reasonably coincide with visits to the Service Dept! Apple have been very accommodating with their maintenance under guarantee but the machine remains a DOG ( or possibly a lemon? )

    any other ideas other than venting my frustration with an Axe??
    Last edited by Khandakulu; 11-06-2019 at 03:38 AM.

  5. #5
    Late 2015 imac - real dog of a machine - help!
    chscag's Avatar
    Member Since
    Jan 23, 2008
    Location
    Keller, Texas
    Posts
    58,910
    Your Mac's Specs
    2017 27" iMac, 10.5" iPad Pro, iPhone 7+, iPhone 8, Numerous iPods, Mojave
    Rep Power
    53
    Upgrading to Catalina when a machine is not running as it should be was not a good idea. Also, I suggest you get rid of AVG since it is known to slow things down and since there are no viruses in the wild that can infect your Mac, it's not needed. You only need to run a Malware scanning program once in awhile to make sure you haven't picked up any malware. And no, malware is not the same as a virus.

    Also I would remove Flip4Mac since Microsoft long ago has given up support for it.

    Can you tell us why the logic board was changed?

  6. #6
    Late 2015 imac - real dog of a machine - help!
    Rod's Avatar
    Member Since
    Jun 12, 2011
    Location
    Melbourne, Australia and Ubud, Bali, Indonesia
    Posts
    5,451
    Your Mac's Specs
    2015 MacBook Pro Retina 13" macOSX 10.15.1
    Rep Power
    14
    Late 2015 imac - real dog of a machine - help!
    I think I would try booting up in Safe Mode and see if any of the problems you mention persist.

    Disconnect any peripherals you may have first.

    Power down your Mac.
    Turn on the Mac.
    Press and hold the Shift key as soon as you hear the startup sound.
    Hold Shift until the Apple logo appears.
    Wait for OS X to boot in Safe Mode.
    Log in.
    Reboot to return to normal operation.

    If the core system works ok with no spinning beach balls etc then it's a software problem. If not then it is a probably a hardware problem.

    Sent from my iPhone using Mac-Forums
    I used to be conceited but now I'm perfect.

  7. #7
    Late 2015 imac - real dog of a machine - help!
    pigoo3's Avatar
    Member Since
    May 20, 2008
    Location
    U.S.
    Posts
    41,368
    Your Mac's Specs
    2011 17" MBP 2.2ghz, 16gig ram, OS 10.11.6
    Rep Power
    43
    Quote Originally Posted by Khandakulu View Post
    1) Possibly although Diagnostic restart and Disc Utility first aid showed nothing ( it did sound a bit scratchy though when the diagnostic spun up the disc)
    3) See 1 above
    A "Diagnostic restart" and running "Disk Utility" are good things to do...but hardly what I would call complete "maintenance". Download, install, and run the free maintenance app called "Onyx" (don't make any changes to it...just run the default settings).

    If this computer had a logic board replacement...that's pretty much the "guts" of the computer. Having two bad logic boards (original & replacement) is statistically pretty slim. 2015 iMac's are not easy to get inside...if the drive is only 25% full...this still leaves the possibility of a bad internal drive. I would focus my efforts on the internal drive.

    Since the internal drive is only 25% full...I would create a new partition...install a fresh copy of the macOS onto that new drive partition...then reboot the computer from that new partition. If the computer is still sluggish after this...I would try replacing the internal drive next.

    - Nick
    - Too many "beachballs", read this: Beachballs
    - Computer seems slower than it used to? Read this for some slow computer tips: Speedup
    - Almost full hard drive? Some solutions. Out of Space
    - Apple Battery Info. Battery

  8. #8
    Late 2015 imac - real dog of a machine - help!
    ferrarr's Avatar
    Member Since
    May 21, 2012
    Location
    Pawtucket, RI, US
    Posts
    6,855
    Your Mac's Specs
    L2014 Mac mini macOS 15, iPhone 8+ iOS 13, 12.9" iPad Pro 1 iPadOS 13,  Pencil 1
    Rep Power
    13
    Can you grab EtreCheck, EtreCheck, run it and post it here? It may help diagnose any issues?


    Sent from my iPad using Mac-Forums
    -- Bob --
    Please backup. Everything has a life cycle, unexpected and warning free. Nothing will last as long as you want it to.

  9. #9
    Late 2015 imac - real dog of a machine - help!
    iggibar's Avatar
    Member Since
    Apr 20, 2009
    Location
    Cleveland
    Posts
    4,211
    Your Mac's Specs
    yeahhhh...might need to look at my signature
    Rep Power
    15
    Those really sound like problems one would come across if there was an SMC issue. Have you tried resetting it? RAM issues cause so many of these problems, and totally can bring a system to a stop if matched with SMC issues. I would try resetting the SMC and see if there's any change in performance.

    This is an SMC link straight from Apple's website:How to reset the System Management Controller (SMC) on your Mac - Apple Support
    3.0GHz 10x Mac Pro 6.13.46GHz 6x Mac Pro 5.12.66GHz 4x Mac Pro 4.12.2GHz i7 15" MBP 15.12.3GHz i7 15" MBP 11.32.8GHz i7 13" MBP 11.12.66Ghz i7 15"MBP 6.22.4GHz 15" MBP 5.12.4GHz 13" MBP 7.1

  10. #10
    Late 2015 imac - real dog of a machine - help!
    pigoo3's Avatar
    Member Since
    May 20, 2008
    Location
    U.S.
    Posts
    41,368
    Your Mac's Specs
    2011 17" MBP 2.2ghz, 16gig ram, OS 10.11.6
    Rep Power
    43
    Great idea iggi...definitely worth a shot. Sometimes it's the easy stuff we forget about trying. Lol

    - Nick
    - Too many "beachballs", read this: Beachballs
    - Computer seems slower than it used to? Read this for some slow computer tips: Speedup
    - Almost full hard drive? Some solutions. Out of Space
    - Apple Battery Info. Battery

  11. #11
    Quote Originally Posted by pigoo3 View Post
    A "Diagnostic restart" and running "Disk Utility" are good things to do...but hardly what I would call complete "maintenance". Download, install, and run the free maintenance app called "Onyx" (don't make any changes to it...just run the default settings).

    If this computer had a logic board replacement...that's pretty much the "guts" of the computer. Having two bad logic boards (original & replacement) is statistically pretty slim. 2015 iMac's are not easy to get inside...if the drive is only 25% full...this still leaves the possibility of a bad internal drive. I would focus my efforts on the internal drive.

    Since the internal drive is only 25% full...I would create a new partition...install a fresh copy of the macOS onto that new drive partition...then reboot the computer from that new partition. If the computer is still sluggish after this...I would try replacing the internal drive next.

    - Nick
    HI apologies for not responding sooner - I had a few things to do and i tried a few things . thank you for your assistance.

    I have downloaded the latest ONyx and run - it - all clear
    I ran a Malware check - all clear . I have removed everything that I don't regularly use , including AVS, and everything that doesn't operate in Catalina
    I have previously ( with the assistance of Apple Support) re-installed the operating system ( before updating to Catalina - problems have been similar with all the recent versions of the OS.
    I had previously had "flashing pixels" in a band across the screen but haven't noticed it so much lately since the new motherboard. ( Maybe I don't even notice it any more!)
    I have two external HDs attached - one for Time machine and one for filing my photos (RAW ( Lumix version) and .jpg )
    I started in Safe mode and that did seem to help a bit but limited what i could do, even in mac Photos. However it might have beenone of the rare periods of good performance

    Problems are intermittent but more problem times than good times. Lately it has been very slow to start, the bluetooth keyboard and touchpad crash ( I now have them connected by cable) and the system often locks up,(Much of this has been ongoing for years) , necessitating a hard shut-down (hold down the on-off button- probably 3+ times a day when busy) . The "spinning wheel" is a regular visitor to my screen and sometimes it doesn't even bother to show up. If I leave the machine sleeping overnight it misbehaves- as when I leave it unattended for a while, so I have to shut down when I am not using it and power up when I sit down to work on it. Sometimes it does not switch off when I shut it down and I have to crash it and start again when I try to log on. Fun and Games!!!

    I believe I know how to partition the hard drive but am not sure where to get a fresh copy of the OS.Please advise. Presumably I can operate my computer as normal, with full access to my other photoediting software
    I am not sure that this is going to help though, in the light of everything else that I have tried. My suspicion is that there is something wrong with the hard drive - an intermittent problem that doesn't seem to register in any of the checks .
    Replacing the HD seems the only remaining thing to do... apart from replacing the iMac entirely.
    Thanks again for your kind assistance

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Is this Imac a good deal? Late 2015.
    By paulwgraber in forum Apple Desktops
    Replies: 4
    Last Post: 10-29-2018, 03:19 PM
  2. Late-2015 27" iMac insides...
    By phospholipid in forum Apple Desktops
    Replies: 4
    Last Post: 03-13-2018, 05:38 PM
  3. New iMac, reports as Late 2015
    By MangoMike in forum Apple Desktops
    Replies: 3
    Last Post: 06-28-2017, 12:53 PM
  4. Win 7 on late 2015 27" iMac 5k Retina.?
    By CaptainMorgan in forum Running Windows (or anything else) on your Mac
    Replies: 5
    Last Post: 04-14-2017, 09:22 PM
  5. Performance a bit slow on my iMac (5K, Late 2015)
    By bbnck in forum macOS - Operating System
    Replies: 48
    Last Post: 02-13-2017, 07:12 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •