Mid 2011 iMac Graphics Problems with Yosemite

Nope there is nothing useful (yet) on that page, just this statement: "The same is true for many of the other graphics issues that have been reported, from Yosemite not identifying the right graphics card to weird colors and shapes appearing on screen. It looks like you're going to have to wait those ones out."

I'd rather say that those seeing those squares onscreen and have their Mac's freeze on Mid 2011 iMacs with ATI Radeon GPUs could solve the issue by turning off transparency for the moment.

I'm so frustrated as my issue still there. Tried to re-install Mavericks, get memory error and failed. Now could not boot to Yosemite even, very regret for the update! 😢

Hello,

I have a 21.5 iMac Mid 2011 (AMD Radeon 6770M) and am going through the same graphical issues. Mavericks in everything worked normally, but after installing the Yosemite the problems started. I have not had any trouble with blocks on the screen, but every time it happens the problem of lock screen and I can not interact with the OS, just the mouse cursor moves. Already reduced the trasparência already updated the flash, I tried a lot. I am also in Yosemite Beta Program and I've done the upgrade to 10.10.1 but nothing worked. Already did a hardware test which showed that all components are in perfect working condition. Has anyone ever got any solutions?

I'm in Brazil and so far no one here can help me.

Sorry for my english. Rs.

Friends, problem solved.

I uninstalled Flash Player using the official removal tool from Adobe, my Mac and really graphic problem disappeared forever. I think the problem was solved. As a small little program can destroy an entire OS rs. I hope this solution solve for you too.

In my case uninstalling Flash did not solve the problem when transparency is ON. The only fix in my case is turning transparency OFF. I worked today for about three hours with Autocad 2013 and not a single display issue. Also watched some movies with Amazon Prime and no problem at all, all this with transparency turned OFF.

Check this out: iMac (27-inch): AMD Radeon 6970M Video Card Replacement Program - Apple Support. It's good up to 4 years from the date of purchase.

I had the same problems after upgrade to OS X Yosemite. Your tip of turning "Transparency" off worked for me too!

Thanks for the tip.

My System:

OSX Yosemite

Version: 10.10 (14A389)

Model: iMac (27-inch, Mid 2011)

Processor: 2.7 GHz Intel Core i5

Memory: 12 GB 1333 MHz DDR3

Graphics: AMD Radeon HD 6770M 512 MB

Hello again and yes, my system was locked down again today (transparency ON + uninstalled flash). I am back to transparency OFF. Adobe Flash was NOT at the root of the problem.

This was posted on the 'blinking pixels' thread, but I will repost it here and try to delete it from the other thread. FYI.....

OK! So heres MY deal!!!
I had mentioned that I had been in contact several times with a senior apple rep in Ontario. Had had given me a CS # that would extend my applecare for thirty days, and cover repairs. My mid-2011 iMac has been in the local Mac shop for 11 days or so, and today I was told it was ready. As stated, the drive would not read any OS X install disk, so I worked it off my freestanding optical drive. Long story short-all of the "fixes" and wipes and Adobe conflicts etc etc that folks (including me) have posted are a bunch of (some, and some not) educated guesses, trying to get a fix or workaround. End of story, Radeon cards are warrantied for FOUR years!!! So, the super (internal) drive was replaced, as was the Radeon 6770 Card. Brought it home, and been up for a while, and its purring like a itten, with no apparent conflicts, no artifacts, just smooth sailing.
I whined and b**ched and finally got a tech who was apparently right-the 10.10 DL somehow affected something in the architecture of the graphics function, damaging the actual card. So, with a new card, and a new drive, I'm keeping my fingers crossed, but I must say, that when you finally get ahold of someone that KNOWS the product, things get much easier. I hope that (1) this puppy keeps on taking a lickin and keeps on tickin, and (2) y'all get some relief SOON. BTW, the local tech AGAIN stated that there is a hot fix called 10.10.1, but that it was not out for consumption yet, whatever that means!
Good luck, and I hope to stay absent for a while!

F

(I tried to remove the repost of the other thread, but it has been on too long. Sorry. Someone will catch it and remove it. Just trying to pass on info relevant to the cause.)

kocojim and gunnyst:

I have the same 2011 iMac and graphic card but had the card replaced a while back. I can run with transparence activated without a problem. It appears you have a bum graphic card. If you still quality for the recall I suggest you take advantage of it and get the card replaced before it goes out entirely like mine did.

Sorry, but why would Mavericks run without any issues whatsoever at that point? I'm not a heavy user, but I'm occasionally running games: that would be quite graphics intensive but isn't shaking the system at all... 😉

IS THIS microphone ON? CAN YOU HEAR ME? TESTING!

Like old toad just before your post said, the Radeon cards are warranted for FOUR years, which makes a 2011 Mac with the Radeon card eligible for a replacement. Thats what I had done, and also, old toad. My Mc has been on since about 4pm yesterday, and NO HINT of pixel, or any other problem.

Try it. You'll like it. Keep calling Apple and asking where you can get a CS code to get your card replaced. Keep asking for a 'higher level' tech, until you get someone who knows what you're talking about. AND, if you search this thread, as well as the 'blinking pixel' thread, someone had posted the link to the graphics card issue with a link to the post, which tells you ow they got their card replaced.

Thx, OldToad, for that. I had my Mac in the shop-11 days, but the tech had given me a 'cs code' which re-instated and extended my applecare for 30 days. The tech told me that, as best he has extrapolated from hundreds of calls, is that (?) it appears that the Radeon cards are starting to fail, and in as much are corrupting/conflicting the software. I thought the opposite, that the software was damaging the hardware, but he sees it the reverse way. since that cards are under their own warranty for 4 years, they are replaceable until 2015. (re a 2011 Mac.)So I'm convinced, as it sounds like you are, and the engineer/tech was 'pleased he could be of help' RE the graphics card replacement. A great guy, and I'm grateful!

(PS- he admitted that for weeks he has been swamped with 2 consistent call types on yosemite; 1-how do you make this or that work, and 2-what is up with this graphics problem!) Said its been wall to wall at his office, and all of the service centers are under a heavy load right now!

Glad it worked for you.

But in case you missed my previous posts, I'm running a DIY Fusion Drive and have definitely lost any kind of warranty there ever was on this machine.

Also the issue MAY be hardware related, as well as software related (which I tend to). Changing the underlaying hardware may have fixed this for you and COULD have you believe this to be an issue of broken hardware only, but even the very same model of iMac (and especially repair parts) does not necessarily imply the use of the same revision of the logic board.... 😉

Understood. But even though you may have taken yourself out of applecare, in as much as the card itself is warranted for 4 years, it seems like if you can get the card replaced from Radeon, then have yourself (?) or a mac shop install it. It certainly couldn't make things worse.....or could it?

Just a thought. 4-5 folks so far have said that replacing the card fixed their issues. So far with my Mac, so good with the new hardware.

✅