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Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
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Troutdale, OR
Hello, I have a 2011 iMac, running High Sierra, and have gotten a weird static like graphics corruption that happens somewhat intermittently. I was able to do a screen recording and uploaded it to youtube so you know exactly what I am talking about:


Do you think this is something related to high sierra, or is it an indication of an impending failure of my iMac? Has anyone else seen anything like this.

FYI, I have seen this while both using iTunes & Safari.

Thanks for any insight.
 
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Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
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Troutdale, OR
it is a 21.5" 2011 iMac, with an AMD Radeon 6770M (512 MB) which as far as I know is was not subject to any recall or factory defect.
 

FNH15

macrumors 6502a
Apr 19, 2011
822
867
it is a 21.5" 2011 iMac, with an AMD Radeon 6770M (512 MB) which as far as I know is was not subject to any recall or factory defect.

I had the Radeon 6770M (512MB) card in my late 2011 27'' replaced twice because of this issue.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
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Troutdale, OR
I had the Radeon 6770M (512MB) card in my late 2011 27'' replaced twice because of this issue.

OK. My mac is now years out of applecare, so i am probably sunk. I will hopefully wait our the next High Sierra update anyway, but will start planning for a 2018 replacement if it lasts that long.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
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Troutdale, OR
Well, I loaded the update to High Sierra, and am still getting intermittent graphics corruption. I am positive it is the hardware that is giving out.

The question now is should I take the iMac to apple (it is almost vintage, and will be classified as such any day), order a used replacement ($300+ when I looked) to install myself, or simply cut my losses and start looking for a new computer?

I have a copy of apple's hardware diagnostic test that I acquired, and it shows the graphics card as ok, so I am not sure if I would be wasting my time or not taking it into apple.

In addition to the failing graphics, the dvd drive has been inop for a few years. I currently use a USB bluray drive instead.

Right now the computer is still operable (with minor graphics issues) so I may be able to nurse this until the iMac/macbook pro/mac mini receive the next updates.

I am torn on what model computer to replace the iMac with as well.
 

dcmaccam

macrumors 6502
Sep 14, 2017
274
51
West Coast of Scotland
Does the corruption happen all the time or very intermittently ? I assume you have some sort of backup ? Did it only appear when you went from you previous operating system to High Sierra? Maybe worth going back to previous operating system ! Might be with a shot. may keep it going a bit longer.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
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Troutdale, OR
the corruption will clear on a reboot, at least for a while. There is no good way I have found to cause it.

From what I can tell it isn't a common issue for others using High Sierra, I thought is was hardware but the apple service diagnostics program I obtained all show passing, even after running them continuously for two hours. (Of course, using that app requires a reboot that may be masking the problem.)

I am not too sure of my next steps. I do have a backup, so if the computer completly fails tomorrow I will be ok, but if possible I would like to fix the issue (depending on cost) and have the computer last a little bit longer, for at least one more year.
 

dcmaccam

macrumors 6502
Sep 14, 2017
274
51
West Coast of Scotland
How frequently does this happen once a day, week,month ? Before you installed High Sierra were you running El Capitan or Sierra. One thing to try is restoring the system from a previous installation/backup that wasn't High Sierra. If the system fails then it looks like hardware. Just try to confirm fault by a process of elimination.

Don't think it is worth fixing if it a graphic card failure unless you can source a cheap card. My AMD Radeon HD 6970M 1 GB video card was replaced, fortunately under warranty, The cost of that card was put a £500.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
368
Troutdale, OR
Every few hours of computer use the issue appears, sometimes right away, other times it doesn't show until I think the problem finally went away, then it reappears. It started with High Sierra, although I vaguely recall it happening once with Sierra, I think.

I don't remember if I was High Sierra install day or a few days later that the problem became more prevelant. I tried to reinstall high sierra from scratch multiple times to fix the issue, using both the internal HDD & external SSD using internet recovery mode to get a known good copy of High Sierra direct from apple's servers.

I am pretty sure at this point it is the hardware failing, despite the fact that the Apple Service Diagnostics are currently not showing an issue with the graphics card. I expect that many others with the same computer configuration as mine would also have the error, but there is no information online showing it. Others on reddit and other forums have chimed in saying that their _____ mac did that before the computer died completely.

Load on the graphics or CPU does not seem to affect it. Sometimes if I go to full screen mode and back again to windowed mode (or connect an external monitor) the issue will temporarily stop for a bit. There is no consistent way I have discovered to trigger the graphics glitches.

The graphics glitches appear on both the iMac monitor, and an external one, ruing out the iMac display itself. (The screen capture would not show the issue if it was just the iMac's display.)

I've pretty much run out of ideas to try without opening up the computer to replace the graphics card, which as you point out would be stupid expensive.

Right now my plans are to keep using the computer until it either completely dies, or I am in a position to purchase a new computer and sell this one for parts, assuming anyone would want it for that purpose.
 

DesterWallaboo

macrumors 6502a
Sep 7, 2003
520
726
Western USA
If you are brave and have some basic electronics expertise, you can actually buy a video card from off of Amazon for your specific model and replace it. It's a bit tedious, but doable.
 

stustanley

macrumors newbie
Apr 29, 2008
1
0
I'm having this exact same issue on my mid 2011 27" iMac (also AMD Radeon HD 6770M 512 MB). It started appearing right after upgrading to High Sierra.

On that basis I've been working on the assumption that it's not a hardware issue - else I would have expected to see similar issues in the previous OS version. I'm sure I've read somewhere that apple have changed how the windows render now and so my working theory was it was something to do with that and/or the driver supplied for this particular graphics card - hoping that it gets fixed in an update
 

Bananaj

macrumors newbie
Feb 5, 2011
4
0
I've got exactly the same issue on a mid 2011 iMac (21") since High Sierra update. Definitely a software or graphics card driver issue.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
368
Troutdale, OR
Thanks for the information that some others are also experiencing this issue. Of course, I have no idea if it is really a software issue, or hardware failing, but it hasn't been corrected so far if it is a software issue.

I wonder if the new software in High Sierra is pushing the graphics card enough to now show this issue, when previous versions don't show it because they don't work the computer as hard.

Either way, it isn't cost effective to try to fix (if hardware), so I will just keep using it until it either dies on its own, or is fixed via software. (I keep checking with each update to macOS.)
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Looks like a hardware issue for me. If the video is pretty much representing the glitches you are facing everything, then it looks like the GPU is dying. (VRAM issue usually won't affect that large area, but start with a little square block. Also, since it can be captured by screen recording. That means it's the GPU rendering the screen with those noise, but not faulty VRAM unable to display the correct image properly).

Another easy way to test if it's hardware failure is by installing another OS. You can do it as simple as boot from a Linux Live CD / USB, then stress the GPU (no real OS installation require).

Or install MacOS 10.12.6 (or earlier) to an external USB HDD / SSD, boot from it, and stress the GPU.

Windows is definitely a good tool to test if that's because of the poor GPU driver in MacOS to cost the issue. However, the installing process may screw up your current hard driver's partition. So, I won't recommend it for just using it as a testing tool.
 

Bowdown

macrumors newbie
Jan 2, 2018
3
0
Looks like a hardware issue for me. If the video is pretty much representing the glitches you are facing everything, then it looks like the GPU is dying. (VRAM issue usually won't affect that large area, but start with a little square block. Also, since it can be captured by screen recording. That means it's the GPU rendering the screen with those noise, but not faulty VRAM unable to display the correct image properly).

Another easy way to test if it's hardware failure is by installing another OS. You can do it as simple as boot from a Linux Live CD / USB, then stress the GPU (no real OS installation require).

Or install MacOS 10.12.6 (or earlier) to an external USB HDD / SSD, boot from it, and stress the GPU.

Windows is definitely a good tool to test if that's because of the poor GPU driver in MacOS to cost the issue. However, the installing process may screw up your current hard driver's partition. So, I won't recommend it for just using it as a testing tool.

The issue with my IMac was the display. You can do your own test by duplicating the issue and do a copy screen to see if the issues shown on the screen captures.
This is how we detected the issue after replacing the video and hard drive and still displaying the issue.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
368
Troutdale, OR
The issue with my IMac was the display. You can do your own test by duplicating the issue and do a copy screen to see if the issues shown on the screen captures.
This is how we detected the issue after replacing the video and hard drive and still displaying the issue.

I was able to do a screen capture video (using quicktime) and the issue shows on the recording. Pretty sure that proves it is not a display issue, it is either a driver issue (unlikely, as there would be widespread reports from other 2011 iMac owners) or a failing computer/graphics chip.

So far the iMac is still working, with intermittent graphic issues, I am ready to replace it if needed, although I hope it holds out until the 2018 iMac/Mac Pro/Mac Mini models are released (if they are updated by then.)
 

Bowdown

macrumors newbie
Jan 2, 2018
3
0
I was able to do a screen capture video (using quicktime) and the issue shows on the recording. Pretty sure that proves it is not a display issue, it is either a driver issue (unlikely, as there would be widespread reports from other 2011 iMac owners) or a failing computer/graphics chip.

So far the iMac is still working, with intermittent graphic issues, I am ready to replace it if needed, although I hope it holds out until the 2018 iMac/Mac Pro/Mac Mini models are released (if they are updated by then.)

Well you were right. They replaced the HD, video card and display the issue remained. They wanted to replace the logic board but I declined since they offered me any PC for 50% off so I took it. Still have my IMac and did not get charge for the repairs. I did hear one tech say it may be an OS issue with our particular model however Apple will not patch a 2011 IMac.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
368
Troutdale, OR
Well you were right. They replaced the HD, video card and display the issue remained. They wanted to replace the logic board but I declined since they offered me any PC for 50% off so I took it. Still have my IMac and did not get charge for the repairs. I did hear one tech say it may be an OS issue with our particular model however Apple will not patch a 2011 IMac.

I am assuming this was not an Apple Store who offered the 50% off of another computer?
 

nguyenhm16

macrumors newbie
Aug 13, 2004
26
30
I have a 2011 27” iMac with the 6770M graphics that had the same issue, after a while it would lock up within minutes of powering up/rebooting. Replaced the video card around mid-2016 (while I was in there I also replaced the factor 250gb SSD with a 500GB one). It started doing it again this past December.

When I saw that Adorama had the high-end configuration of the late-2015 5k iMac for only $1,400 (originally $2,300), I went ahead an got one — I couldn’t buy a used late-2011 for that price, it would have cost me about $300-400 to replace the graphics card in my 2011, and from what I can tell resale value on these 2011s are not that great because of this issue.

Now I just use my 2011 as a second display using target display mode for my new 5k iMac. It’s the Thunderbolt Display I never ended up getting. So far, there’s been no issue (which makes sense since the display on my 2011 is being driven by the video card in my new 2015 iMac).
 

FirDerrig

macrumors newbie
Jan 4, 2018
11
4
Hello, I have a 2011 iMac, running High Sierra, and have gotten a weird static like graphics corruption that happens somewhat intermittently. I was able to do a screen recording and uploaded it to youtube so you know exactly what I am talking about:


Do you think this is something related to high sierra, or is it an indication of an impending failure of my iMac? Has anyone else seen anything like this.

FYI, I have seen this while both using iTunes & Safari.

Thanks for any insight.

Could you also post a few more bits of information regarding your use of the iMac? Specifically, how much RAM you have installed, the types of apps that you use, and what the machine has basically been used for since you purchased it.

Also, the superdrive failing is not uncommon. It happened on my early 2009 20" and also my wife's Late 2009 21.5". Usually I see the failure on these optical drives with the inability to read DVDs first while still being able to read CDs at least for a time.

From what I have seen regarding the move to High Sierra is the increased demand on memory from earlier versions of Mac OS X and I think that could be at least a plausible explanation for the graphics issue regarding the rendering of the GUI.

Do you use Chrome as your browser at all? This might not be anything to it but I have noticed that Chrome causes increased memory usage and has at least been partially to blame (in my opinion) for ruing earlier Core Duo and Core 2 Duo machines.

Other posters have also suggested reinstalling an earlier version of the OS. I would second that.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
368
Troutdale, OR
Could you also post a few more bits of information regarding your use of the iMac? Specifically, how much RAM you have installed, the types of apps that you use, and what the machine has basically been used for since you purchased it.

32GB of ram (Patriot brand). Normal household uses, web browser (safari), email. The most demanding thing I do is run Handbrake to encode movies into an iPad compatible format. I don't use chrome.

So far other than the odd graphic corruption issues everything else (other than drive the broke years ago) is working fine.

Honesty it's too much of an effort to try and revert back to an earlier os, as it would involve trying to get my apple photos and iTunes files converted to an earlier version, and who knows what it would do to my iCloud documents/apps.
 

FirDerrig

macrumors newbie
Jan 4, 2018
11
4
32GB of ram (Patriot brand). Normal household uses, web browser (safari), email. The most demanding thing I do is run Handbrake to encode movies into an iPad compatible format. I don't use chrome.

So far other than the odd graphic corruption issues everything else (other than drive the broke years ago) is working fine.

Honesty it's too much of an effort to try and revert back to an earlier os, as it would involve trying to get my apple photos and iTunes files converted to an earlier version, and who knows what it would do to my iCloud documents/apps.

Oh well then I don't see why there would be an issue regarding anything memory related. It's nice when people don't use Chrome because that is one of the applications on my "almost hate list."

How much different is High Sierra from Sierra regarding Photos and iTunes? And as far as I know, nothing else has changed that much that would make it too much of a hassle unless of course I am completely wrong.
 

Richdmoore

macrumors 68000
Original poster
Jul 24, 2007
1,973
368
Troutdale, OR
Oh well then I don't see why there would be an issue regarding anything memory related. It's nice when people don't use Chrome because that is one of the applications on my "almost hate list."

How much different is High Sierra from Sierra regarding Photos and iTunes? And as far as I know, nothing else has changed that much that would make it too much of a hassle unless of course I am completely wrong.

I know each macOS/iTunes update has updated the library files for those programs (it causes a delay upon the first launch, as it updates the library files.)

I would guess the files can be downgraded, but I don't know the process or if I would lose any meta data or photo edits.

In addition, trying to convert me SSD back from the new APFS to the old system sounds like a pain. I don't feel that it is worth the hassle to try and downgrade, just to see if it is a macOS vs hardware issue.

If it is a macOS issue, it will get patched. I think there would be lots of reports if it was affecting every 21.5" 2011 iMac models. The evidence so far, although far from conclusive, does not sound like there are widespread issues with my iMac model due to High Sierra.

If it is hardware fault, it will either stay the same, get worse, or just stop booting. A logic/graphics board fix is not cost effective at this point. I have a good backup system in place as well.

My original plan (before this issue) was to consider replacing the iMac once it could no longer run the latest macOS, so I will be happy if it holds out at least until the 2018 iMac/Mac Pro/Mac mini models are updated and I can consider which system to replace it with. I tend to give my old systems to other family members, so I won't be able to this time unfortunately. (I don't want to give them a possible problem computer.)
 

FirDerrig

macrumors newbie
Jan 4, 2018
11
4
I know each macOS/iTunes update has updated the library files for those programs (it causes a delay upon the first launch, as it updates the library files.)

I would guess the files can be downgraded, but I don't know the process or if I would lose any meta data or photo edits.

In addition, trying to convert me SSD back from the new APFS to the old system sounds like a pain. I don't feel that it is worth the hassle to try and downgrade, just to see if it is a macOS vs hardware issue.

If it is a macOS issue, it will get patched. I think there would be lots of reports if it was affecting every 21.5" 2011 iMac models. The evidence so far, although far from conclusive, does not sound like there are widespread issues with my iMac model due to High Sierra.

If it is hardware fault, it will either stay the same, get worse, or just stop booting. A logic/graphics board fix is not cost effective at this point. I have a good backup system in place as well.

My original plan (before this issue) was to consider replacing the iMac once it could no longer run the latest macOS, so I will be happy if it holds out at least until the 2018 iMac/Mac Pro/Mac mini models are updated and I can consider which system to replace it with. I tend to give my old systems to other family members, so I won't be able to this time unfortunately. (I don't want to give them a possible problem computer.)

Fair enough. I forgot about the APFS since my machine doesn't have a SSD and I wouldn't be affected by that. Not to mention I try not to buy HD versions of movies on iTunes that would limit my ability to play them using older versions of the app.

What I would still consider then if you like giving your old systems to family members and if it is some issue in MacOS HS the doesn't get patched for some reason, then downgrading the OS and then still giving it to them would work out.

My wife's 2009 iMac is still holding out with Superdrive failure, WiFi issues (now it's wired to an AP extreme), and slow downs. I think that your machine should still last.
 
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