Red and green square dots?

has anyone actually resloved the issue permanantly?

dgd2000,

Let us know if the drive swap fixed your video problem. This would explain why no artifacts are present when an iMac is used as a monitor only, and why there are reports here that changing the video card and motherboard did not eliminate the problem.

jmf

"The good news is that I could restore everything from my Time Machine backup AND the red and green squares are GONE. Of course, this is only Day Three of my testing, but I'm cautiously optimistic."

jmf,

This is Day 3, and so far the hard drive swap (or cleaning the dust and lint out of the iMac interior) has eliminated the red and green squares. I'll report back if they reappear...

I meant to pass this along last night but got caught up with too many things. Also wanted to say that I did have Apple do the hard drive replacement just slightly before the program ended. Below is some additional documentation I made regarding this issue (pictures included to show most of the graphical distortions I have seen so far).

I ran across some other forums of people observing these issues (pre and post Mavericks).

Links to the additional forums below.

https://discussions.apple.com/thread/3194165?answerId=24452202022#24452202022

https://discussions.apple.com/thread/4018810?answerId=24452195022#24452195022

https://discussions.apple.com/thread/5594740?answerId=24450773022#24450773022

https://discussions.apple.com/thread/5454441?answerId=24450561022#24450561022

I completely agree with browsers intensifying the issue(s) but I have observed the issues with

Firefox/Safari/Chrome (separately so it doesn't appear to buggy browser apps, instead more likely

related to a draw on memory).

I have not really paid significant attention to the Activity Monitor since Mavericks and I fell like I have

accidently come across something that may be useful? After searching online I am not the first to

notice these "features" as of Mavericks. My kernel_task is using up over 500MB on launch and hitting

close to 900MB when the iMac starts to freak out. Additionally I see the the

com.apple.IconServicesAgent is using up 150MB on launch. Others are also noting that Mavericks is

hogging a ton of memory in either/both processes. Basically it seems that these features were observed

in different OS versions but Mavericks is likely drawing significantly more memory that just pushes

the bug out of control?

To get everyone on the same page regarding the features... I have seen several "features/bugs" now with

the 27"iMac. As noted recently I have seen some very strange features in WoW/Minecraft and have

also observed a strange pixelation in Bioshock Infinite.

In my experience, the pixels/squares are the start of the issue. I usually see them shortly after

video/gaming. They usually start as blue squares, progress to red squares and are clustered together in

a specific pattern. After that they progress to different colors and are less clustered at that point.

After the pixels get going, then I start seeing the more interesting/crazy features. I have seen massive

blocks of browsers just completely re-organizing itself. Basically taking text/colors and rearranging in

some strange pattern (makes english look like a new language). I have also observed bands of

colors/pixels over the top of active applications.

I believe that all of these features are somehow related and get progressively worse with increased

memory usage (whether that is the logic board, gpu, video card, RAM I have no idea).

Below I have added some screenshots in reference to many of the features that I now see.

Hopefully some information here will be helpful

Multicolored Squares (Browser is also white due to flashing normal/white based on some other issue.

Browser did have information on it but would fade to white completely at times):

Blocky Image (nonsensical language):

Vertical Stripes (Observed through multiple applications):

Regarding a solution, I suppose I have likely found the best solution that I will ever find to this issue.

I recorded evidence of the original video issues that I had before the squares started to appear. Although I was out of warrantee Apple was completely fine with replacing my graphics card at that point (as noted previously that did not fix my issue in any way shape/form). The new graphics card was covered for another 90 days in which I returned about a month ago, then finally again today.

Last night I observed the squares, a massive slow down and a bunch of very odd graphical features. Once again the 27” iMac passed the diagnostics with flying colors. Also the store could not replicate the issue when I left it there for more than a week. Since I documented the issues with several videos/images and since this issue is just taking up too much time they made an offer. I can either get another graphics card installed or they agreed to credit me $600 for any new purchase. Seeing that is about 25% of the original sales price and I have used my iMac for 3.25/3.5 years now, I think I might just take the plunge into another (obviously maximum coverage in case of issues again in the future).

I don’t know if they will do this for others who are not covered. If you are still covered I would highly suggest to get it in as quickly as possible and record/document everything that you see. If recording video make sure to record using a different device as some people have suggested that they don’t see the issues when taking video of their current screen.

Not a perfect solution at all but maybe helpful?

wow... yeah you should definitely take the credit toward a new purchase. Doesn't sound like there's a silver bullet coming from the company that designed and built this generation of plagued systems.

I think it boils down to how sensitive the hardware is from pollutants, heat, contaminants, even altitude in some situations; and how this run of hardware and their remaining supply chain for this gen isn't working out.

If they could fix this with software, you'd have to think they would've attempted it already.

Interesting find niklesko. I find my kernal_task at 940mb and iconservices at 230mb, and I just rebooted last night (and colored squares are all over my screen).

jack fox as I have mentioned many times, I installed a brand new hard drive and a fresh copy of mavericks. the colored squares were greeting me as soon as I logged in. It is NOT 3rd party software, it is NOT the hard drive, many of us had this issue plaging us well before mavericks (since 10.7 for me), and we have seen a few people get their graphics and logic boards replaced multiple times without solving the issue. It is clearly an apple system or driver bug with the 5750 that we all have in common.

Disabling quartz extreme kept the squares extrememly minimal and zero crashes for TWO WEEKS. I needed graphics accel for some video editing last night so I turned it back on. Within hours, crazy blotches are back. I bet I'm crashed by the end of today.

I tried everything. Apple even replace my logic board. The new logic board failed. The second logic board also had an unrelated problem. Subsequently I am now having my Macbook replaced.

The plague is a hardware issue that is probably made manifest and agitated by new software / operating systems and full up HD's. I toiled with the problem for 12months as it got more and more aggressive. Eventually my computer wouldn't start unless it was plugged in and then finally it failed all together. fortunately I back everything up.

If you live in Europe and your comupter is less than 2 years old Apple may repair it even if it is out of warranty. Under new EU legislation computers are expected to work without issue for at least 2 years...

Has nothing to do with new OSX, etc. I had these pixel glitches with a fresh copy of my original OSX DVD disks when I back-installed last month. The first 2 years of ownership it was predominately glitch-free, definitely the first 1.5 years. If it's a software or driver bug, why didn't it show itself in the first 1.5 years of ownership?

soulnational are you sure they are the original disks? Which system version?

I thought they started with later updates to 10.6 or 10.7.

I would believe deteriorating video ram or other hardware, but with several reports of graphics + logic replacements and issues returning that doesn't make sense.

One of these days I will have to open and remove the LCD panel and hit things with a vaccum as that seems to be the best solution so far, but I just don't believe it; if dust was blocking airflow and things were overheating, you would hear the fans ramped up. Not to mention the reports that things are worse when it is cold.

It is just frustrating with no clear solution after years, and this mac still very much a decent system otherwise that even if I wanted to updgrade would resell for a good chunk without these problems.

yep, my original disks, 10.6.

Again, I'm not picking a side to fight for. I wish it was a driver bug... I just look back to the first 1.5 years of flawless performance. The machine was new. Even though it looks new externally today, the guts of this machine require a sterile environment to work for 10 years flawlessly.

...and I did hear the fans ramp up for a period of time this past summer, like an old dog, this machine wouldn't cooperate. Wish I paid attention and cleaned out the case. -Which probably did a number on my sensitive components. I'm telling you, dust is my enemy. And, if you live in a studio apartment--like most of the world does--then you're likely exposing your iMac to micro particules of cooking greases and smokes.

I've seen how Intel makes their chips. No one is cooking dinner 18 ft away. These machines need the cleanest possible conditions to work flawlessly. I'm amazed my iPhone runs as well as it does considering the abuse I put it through.

And a vacuum might not be effective. Compressed air, preferably filtered or the canisters they sell at office supply stores.

would love to know of cleaning solutions techs are using. That would be my last ditch effort to ressurect the innards of my iMac.

Anyone know if the Tunderbolt Displays have fans or vents that draw air?

moving on to MackBook Air in the future. Or maybe a Mini. But never again an iMac. My replies in this forum speak to the reasons why.

Add a charcoal filter strip to your new iMac's intake. Might save you from spending time at this forum and/or the Genius Bar....

Some have pointed out that there are multiple other discussion threads in the forums about this issue.

Has anyone here tried the solution proposed in this post?

https://www.dropbox.com/s/yhus1gjiidodsh3/Screenshot%202014-01-13%2012.56.21.png

Also, Apple did recall the iMac (27-inch) Radeon 6970 video card, even though it was causing fires or death to children, so maybe there is some hope for us Radeon 5750 users.

http://support.apple.com/kb/TS5167?viewlocale=en_US&locale=en_US

I think early in this thread there was a BIOS hack that worked for a bit only to isolate him/her to a specific OSX version, and then it fell apart because the glitch came back regardless of the OSX version or hack introduced. And then there was some expressed ideas about dissabling quartz, etc.

The best thing I've found so far is to eliminate using Safari. And dissable all your energy/sleep modes. Run the device 24/7, and if you shut it off, expect to hard-reset multiple times until the iMac reaches very warm running temps.

One thing I'm going to test is running Safari and all of it's supporting files from a secondary hard drive. If it runs well, then I'm going to build an external HD OSX clean install and see how my system performs running off a remote boot disk--I like that idea. If it works, maybe I do have a corrupt piece of hardware (internal hard drive) or pathway (cable) up to the point of the motherboard.

would be killer if Apple's Diag tools were more intuitive in this nature.

Hello all.

I wanted to let the community know that we too have been experiencing this pixel anomily on our iMac 27 inch Mid 2010 machine for quite some time now. The GF uses it daily for moderate graphic design work and yeterday upgraded it to 10.9.1 hoping it may resolve this issue. It seems to have become worse now. I will be taking a closer look to this in the days to come. One similarity stick out though worth mentioning... the pixels and the freezing / hanging upon restart seem happen most when she is cold. Once she is warm, the ***** seems to run okay most of the day. ecept for the intermittent colored pixels.

Thanks to all for the pile of information contained in this thread. Too bad someone from Apple hasn't responded to it. 😮