Red and green square dots?

I know its a late reply but I have solved my iMac 27" 2010 with Radeon 5750 video card.

I had a kernel leak or something due to an error/fault in both Sophos (anti-virus) and also Little snitch (free). I deleted sophos and it was better. I still had green and purple squares on my screen and then i downloaded the little snitch installer/uninstaller and removed it. After my next full power cycle/restart it was cleared.

I had to remember what the last few programs I had altered or installed. I had both these programs installed for over 5 months. So, it took 6 months to fail on my computer.

If you think you have some kind of junk/spam/virus/firewall programs that control a lot of behind the scenes stuff, please erase it and re-install it or use something else.

12 hours in and still no more green and purple squares! The squares ended up being permanently there and changed when i vigorously waved my mouse or adjusted the screen brightness. it would eventually crash my imacs video card and everything else would still work in the background (plex, media server - music, itunes - etc)

Please Reschool, update in a few days, to let us know if it just chance... or real ;-)

Thanks

THis this above pic is what used to happen.

Now, I've Left my Mac running constantly since then (like I used to) and had zero further pixels flashing green or purple.

IT would usually have been 1/3 covered in coloured squares By now.

I Also upgraded to yosamite. But it was doing it since half way through Mavericks Life span.

I Don't think it was the OS. I believe the programs (one or the other) have a scripting flaw (intentional or otherwise) that leak kernel resources until the video cars is overwhelmed and freezes while everything else goes on in the background. The mouse cursor would also still move but would be unable to click on anything as was also the case with the Keyboard.

I Left my Mac running since and had zero further pixels flashing green or purple.

IT would usually have been 1/3 covered in coloured squares By now.

I Also upgraded to yosamite. But it was doing it since half way through Mavericks Life span.

I Don't think it was the OS. I believe the programs (one or the other) have a scripting flaw (intentional or otherwise) that leak kernel resources until the video cars is overwhelmed and freezes while everything else goes on in the background. The mouse cursor would also still move but would be unable to click on.

Google my solution people. i cant remember where i posted how to fix it.

Fix.

Was delete Sophos and Little Snitch. or similar. recent programs. they were stuffing it all up. Runniungsfor 3 days now since. NO MORE SQUARES!

its a kernel leak. no further firmware avail.

this really helped me thank you

Fingers crossed this worked like a charm. I've only been back up and running for a couple hours now, but so far there's been no angry dots.

Been having the same problem last 4 months.

Tried everything I could imagine and nothing worked until I saw your post and uninstalled Little Snitch.

iMac 27" mid 2011 - AMD Radeon HD 6770M.

Thank you very much, you just saved my mental health 😉

Very happy for you Reschool. But I don't have Little Snitch or Sophos installed... Last night I've done a clean install of el Capitan and update at 10.11.6. Work like a charm, for a few hours. But quickly squares have return, and this night a crash. Nothing more installed than OS X.

I continue to think of a flaw with Radeon card... :-(

Alex.

Maybe and maybe not - you are aware you are posting to a thread that is over 4 years old (started in April 2012 about iPhoto under OS X 10.7.3) about totally different hardware, OS and Photos software - if you what to discuss current issues you need to start a new thread with the specifics of your issue -- for help is composing a good question see Writing an effective Apple Support Communities question

LN

Dear Larry.

It's a 4 years old post about a 5 years old iMac with display problem. The first post "suppose" a Photos problem on 10.7.3. But lot of people had problem with other OS and not for Photos only.

Why give up an exchange rich in information ? Because it's 4 years old ? Nonsense !

I change my iMac, before to bake the graphic card and/or sell it, I'll test with 10.9.6 OS X for a few weeks. I will post the information here.

Because a search point quickly this thread. An exchange grows rich by the various additions, it does not age like a computer ! No ?

Alex.

I've had this problem as well. The first occurrence was in 2013 and I did the OS reinstall, disable transparency, even installed Windows (bootcamp). The problem even manifested in Windows (actually worse since it would lock up Windows). Figured it was a hardware issue so I baked my graphics card and viola! no more crazy squares dancing on my screen. Flash forward to Nov 2016 and the squares are showing up again. The baking solution isn't permanent but it did seem to work for a long time. I use my computer daily for work (software developer) so it takes quite a beating. I'm sure that baking the graphics card will solve the problem although if I'm going to go through that process again, I'd rather replace the GPU instead. Has anyone had any experience with replacements? I'm guessing since this is such a wide-spread problem, that buying the same graphics card from ebay or amazon will more than likely have the same issue.

I've been following this thread for months, on and off, and have tried quite a few things. I'm not a baker, so I'm really glad I found this click "Reduce Transparency" tip! 4 days later and not a single square has shown up. I'd say "knock on wood" and "crossing my fingers" but I think this indeed fixed it for me. 🙂

I'm having this on a new MacBook Pro Retina Mid-2015 model. Only a few months old (bought it just after the 2016 came out). Still well within warranty. Apple reps are scratching their heads.