Red and green square dots?

I did read the baking trick on some other forums and websites, so I realized that it's not unique to the iMac. However, (and not to be argumentative), but are you sure it's being reflowed? Has anyone probed the solder with a toothpick or something near a large component with a big fillet, like a capacitor or connector retention pin? The reflow profile is pretty specific.

As an update, I spent some time at the Genius bar today. The problem immediately appeared, to my relief, after hauling the beast in there. (Next time I'll get a folding luggage cart.)

The tech booted from a diagnostic server over the network, and found nothing wrong. He then network booted from the latest OS (Yosemite, as of the time of this writing), and we ran a bunch of graphics-intense applications for several minutes, using multiple windows of Grapher and some visual stuff on iTunes. He speculated that there might be a corrupt file somewhere that was damaged during the latest OS upgrade, so he reformatted and partitioned the drive, and loaded a fresh copy of Yosemite from the network.

My installation started with Snow Leopard, and has been updated several times, so it's entirely possible, I suppose.

I'll let it run for a week or so, incrementally loading stuff like my iTunes and iPhoto libraries and various apps, and I'll report back to the group with any results.

I've been using the "defeat-all-energy-saving" setting ploy (along with no-transparency, too) and - despite well below seasonal temps, I've not had any pixilations for nearly a month.

I DO - however - continue to experience "graphics problem" error message, freezes, and restarts.

Also system crawl from RAM "maxing out" - most often, due to Google Chrome Helper massive overloads.

Ordered an additional 16 Gb of RAM - due to arrive any day now - and will report back on the impact of installation.

I'm intrigued by the reports of Apple store $151 video card replacements, and came across an article that reports the video cards from 2011 iMac 27" will retro into the 2010 27" as well:

https://www.ifixit.com/Guide/iMac+Intel+27-Inch+EMC+2309+or+2374+Graphics+Card+R eplacement/9553

Has anyone tried this? Successfully?

I have a Mac Pro from 2009 with SnowLeopard installed. I've had blue squares on my machine on and off the last few days. A few times it even locked up with the mouse still active, but nothing clickable. This morningn I turned on the machine to find this:

I shutdown the machine, tried the hard reset, but this continued to come up after 3 attempts of restarting. So I searched online and found this thread.

I removed the hard drive and put it in a USB case then connected it to my MacBook and the drive was fine. I've already been researching getting a new MacBook Pro to replace both my old MacBook and this old MacPro, so I decided I had nothing to lose by trying the "baked video card" method. So, I removed the ATI Radeon 4870 graphics card and baked it in the oven - 5 minutes at about 425f degrees. After allowing the card to cool, I reinstalled it in the MacPro, turned it on, and voila! Here's hoping that it stays working now! The only problem I had was the plastic cover got just a tad too hot and the fan on the card now makes a clicking sound, but it still works. I'll monitor it for awhile and make sure the fan doesn't fail. I guess I should have put it in for a few less minutes or maybe cooler temp? Anyhow, here are some pics of the baking event:

Top of the card, prior to baking:

Card in the oven. I placed it plastic side down on a piece of aluminum foil.

The card after 5 minutes in the oven. One sticker curled up from the heat (bottom center in photo)

The sticker that has the white circle graphic around the top of the fan came off a bit, sticking onto the foil, and the plastic got a little bit melted - but not too much. Glad I didn't leave it in any longer, but hoping the solder issue is fixed.

After reinstalling the baked card, the system booted up just fine! so far no squares. We'll see how it does overnight as the temps drop down again.

After a year of grumbling through a reappearance of the dreaded pink and blue squares - and lamenting that I had invested so much money into an iMac computer (at $2,200) that only gave me two good years, I finally gave in and baked my graphics card. I had never purchased applecare because I believed that Apple had good quality control on their computers. I had reached a point where I could not go any further because my computer kept crashing after bootup.

Reading about the baking idea seemed too intimidating, but today I thought "what the heck!" I took my iMac apart, located my ATI 5750 on a mid-2010 iMac 27 in., and removed it. The hardest part for me was removing the heat indicator from the back of the motherboard. I heated up my oven to 390 degrees, cleaned off the thermal paste on the chip, placed it chipped down on four small balls of aluminum foil and baked it for 7 minutes. After I let it cool down, I placed some new thermal paste (arctic silver 5 - about as much as a grain of rice was placed on the chip and smoothed around by my pinky finger.) I placed everything back together and fired it up and it is as good as new.

If you are concerned about baking your card - I am another in a growing line of people who are saying "it just works." Apple should have provided a recall or some repair program for our community of people who spent top dollar money on inferior hardware. While I am thankful for this forum which has helped me to fix my dead iMac, I had literally made plans to buy a Windows computer for Christmas just so I could have a machine that worked. While the fix did work, this entire experience has left me with a very bitter taste about investing any more of my hard earned money into other apple products.

Well done, Crows8ster. After all else fails to shift the little devils baking is the only way to go. If my experience is anything to go by (baked over two weeks ago, still holding) you will not regret your decision. Like you, I baked for 7 minutes at 390F. However for future cooks I think that the graph provided by pointpeninsular a few posts ago may be interesting. After about a 5 minutes bake some of the felt on the card began to peel off, not earth shattering but I would have prefered it not to happen. If I had my time again, I would bake at same temperature (390F) but restrict it to 5 minutes and make sure the card is placed so the side with the felt is pointing upwards.

For those following this thread.......

I baked my graphics card 4 months ago, and since then have not had a single dot or crash. The cure seems permanent.

This was after taking it to Apple and having them replace the card (which doesn't seem like a cure).

Cheers!

Navwizard

baked video card (ADM radeon 5770M 512 ) on 2011 imac- different instructions from prior posts in this thread.

I have been having the flashing many colors of small squares that comes and goes, occasionally causes crashes, and it has been getting worse over time.

I tried to switch to Yosemite and I had major problems.

I finally bit the bullet and baked my video card today. The mac I own is a A1312 mid-2011 27 inch imac with an ADM radeon 5770M 512 MB video card.

I thought it would be easy because of several references in this thread to using https://www.ifixit.com/Guide/iMac+Intel+27-Inch+EMC+2309+or+2374+Graphics+Card+R eplacement/9553.

This does not work. The 2011 27 in imac is more difficult and different. I found out by pulling the mac apart, removing the LCD panel, then realizing the screws on the video card were on the other side of aluminum frame. I pulled a few screws off the logic board to see if I might be able to figure out what I needed to do to pull it off, but I quickly realized I was over my head without instructions. I put it back together. I had done a little pulling on the logic board. When I restarted, my video problems were significantly worse. Made the machine virtually unusable.

So I was committed to tear it apart and bake the video card.

I found detailed instructions in the 2011 imac 27 in mid 2011 technician guide

which I found searching the web with "imac-27-inch-mid-2011-technician-guide". This PDF is a 400 page detailed document that goes through all aspects of diagnosing and repair this mac.

I had to remove the glass, screen, power supply, dvd drive, dvd fan, airport card, IR sensor, pull out the logic board, and then I could finally remove the 5770M from its frame. I pulled the video card off the heat exchanger, cleaned off the old thermal paste on the processor using acetone, but not the thicker white puffy thermal material over the memory (this white material (~1/16th inch thick) stayed on the heat exchanger, not the video card when I separated the two).

I baked it (card only) for 8 minutes with tin foil on balls crimped on all 4 edges to raise it off the metal baking pan at 390 F in a standard full sized electric kitchen oven. I pulled it out of the oven and let it cool. I applied new thermal paste to the video card but did nothing to update the used white material over the memory (left it as close as it was when I pulled it apart).

I then re assembled the computer and restarted. Amazingly it restarted just fine. And no red and green squares.

Given that I could hardly use the machine before, it is definitely at least a temporary improvement.

I played with the machine for ~10 minutes without a sign of issues.

I did it today because I am heading off for vacation tomorrow and could have ordered a replacement video card while I was away if the baking had killed it or otherwise failed.

So I won't know for several weeks until I return whether its a solid fix, but I thought I should at least get info about following the apple technican-guide

for detailed instructions.

Thanks for the great tip about the Technician Guide reference, Zebratode! I found the mid-2010 iMac Technician Guide at this address: http://www.elvikom.pl/pobierz/p/20748

After 4 years with my 2010 iMac lemon, I am ready to throw it overboard. The first hard drive started to fail just as it reached the 12-month mark, but it luckily was covered by a recall and was replaced for free. That lasted about a year until the red and green squares began to appear. A few months after that started the "new" hard drive crashed and had to be replaced. Miraculously, replacing that hard drive (and wiggling cable connections, perhaps) seemed to cure the red and green square problem -- for about 6 months. This fall the problem has worsened to the point I was ready to give up on the Mac world. I built a new PC last month, got "comfortable" with Windows 8.1, and have moved nearly all of my data and replaced many of my Mac apps with their Windows counterparts. With the nearest Genius Bar over 3 hours away, I have had no support at all from Apple with this problem. I plan to try the video card baking soon, just to see if I can get the iMac to work again. I know I'll never buy an all-in-one computer again, especially not an iMac.

Just for a point of reference, I have had the red and green square problem with Snow Leopard, Lion, and Mountain Lion. I have not upgraded to Mavericks or Yosemite because many folks reported the red and green square problem only got worse. The symptoms I have seen indicate a hardware issue, not a software one. Everything I know about electronics (I'm an electrical engineer) would indicate that baking a circuit board in this manner would not properly reflow the solder and could damage components; nevertheless, I figure I have little to lose if it doesn't work.

I'll let you know what I discover if I do try the baking approach!

I ran into this the first time sometime last year. It was after being away on business and having shutdown my 2010 27 inch iMac. I work from home, it's almost never off. When I came home I booted up and had the artifacts. A reboot however cleared this up, with no re-occurance until about a month ago. And then it would happen every now and then if the display went to sleep. My office gets cold and this is especially true when I'm don't use it and heat it daily.

This morning our power went out and my computers shutdown due to UPS low power. When I came home this evening when booting up I had the artifacts again, and the computer would freeze. Rebooting didn't work, power cycling didn't work. I've been reading these threads for baking for some time now, but have avoided it since the problem did always seem to go away. Today this did't happen so I pulled my iMac apart and cleaned off all of the heat sink paste and baked my ATI Radeon HD 5750 w/ 1G ram. I baked it at 390 for just under 8 mins. My intention was to go the full 8mins, but some of the foam started to peel up and I didn't want to push that any further. I allowed it to cool. Put arctic clean purifier on the heat sink and used Arctic Silver 5 compound. Re-assembled my iMac and booted right up. No artifacts, no freezing. Now this could all just be coincidence as this has happened in the past, but today I do not think so. I think there is enough history here that this process works and hopefully long enough for me to get my moneys worth out of this i7 quad core iMac that i spent so much on in 2010. I do love the computer and up until this issue have had no problems.

Same site I found the 2011 manual.

I have now pretty rigorously tested my fix. It is completely back to normal. Before I baked the video card I had tried to update to Yosemite. I had done so by making a copy of my hard drive on a portable drive, then updating that portable drive so I could test if Yosemite fixed the square dots problem (without making a firm commitment to Yosemite. Instead I found Yosemite completely unusable as several other people have found. The square dot problem was greatly exacerbated by upgrading to Yosemite. I literally could not use the computer running with Yosemite as the operating system.

After the baking I again tried Yosemite. It works perfectly with no sign of red dots.

I've now been using the computer for five days at work with absolutely no sign of square dots.

I consider my problem fixed by baking.

Hello everyone -

I have been trolling this forum for months - since just after the public release of Yosemite. I thought I'd share with others what I have been through...

I have a mid-2011 27" iMac with the Radeon HD 6770M graphics card. I had experienced the random screen pixillations every 4-6 weeks running Mavericks, and a quick reboot would make the problem go away. As soon as I upgraded to Yosemite, the problem grew immensely worse. Pixillations went from a few here and there on the screen to covering up to half of the screen at once. The screen started locking up, even though background processes were still running (I use SpamSieve and it would continue to filter email while the UI was locked up). The only solution was to do a hard power off and power on. This would happen between 4 and 10 times a day! Incredibly frustrating. I had never locked up under Mavericks, just occasional pixillation artifacts.

So, I reinstalled Yosemite as a new install. And I had the exact same problem. I turned off transparency, turned off sleep, everything I could find as a suggestion here and elsewhere. No change. Pixillations and lock-ups continued.

I finally reinstalled Mavericks. First from a Time Machine backup. I continued to have the same problems that I had experienced on Yosemite! I couldn't believe it, since I had never had the locking up on Mavericks before the Yosemite upgrade. So I reinstalled Mavericks again as a new install... And I still had the issues with locking up and pixillating. I did find that if I set the desktop background to a plain light color (like white or beige) it would pixillate less, and lock-ups happened slightly less. Also, if I used a screen saver instead of just blanking the screen (I used to blank the screen when not in use - iMac stays running continuously - always has since the purchase, other than on trips away from home) then the problems seemed to lessen. Not go away completely, but lessened enough to use the Mac a bit more (it was virtually unusable after the Yosemite upgrade).

Finally, last weekend I gathered the courage, resiliency, and frustration to tear my machine apart, remove the graphics card, and bake it in my oven. You should have seen my wife and kids' eyes when they saw that I was actually baking it! 8 minutes at 290 degrees. On aluminum balls, on a pizza pan.

I was fortunate to have recently received a 13" MacBook Air from the college where I teach, and this has become my main computer since the graphics issues arose on my iMac. I don't know if I would have had the courage to bake my card if I had not have had the security of having the MacBook to use if everything "went up in smoke!"

After letting the card cool down, I put on the thermal paste (from Staples) and put it back on the heat sink, then put everything back together. I booted it up...

and it came up fine! I have been using it here and there every day since (so that's 5 days post-bake now) without the first sign of the pixillation and without a single lock-up. Prior to the bake, I was able to force a lock up "at will" by doing anything that was graphically challenging (open a few Finder windows, open a few Safari windows, open Lightroom or Photoshop, play a video in iTunes, open Evernote... just about anything!). I have not been able to do it once yet since baking the graphics card.

So as you can image, I have gone from being aghast at anyone baking their graphics card (I thought it was the craziest thing I had heard, that there had to be a safer and more sensible solution, and that they were experiencing a colossal "coincidence" of good fortune that it seemed to work!) to being a sold-out believer! My iMac is back and I am a happy camper!

Now, the proof is always in the pudding. I am still half-way expecting the problems to suddenly erupt again. Time will be the only thing that makes me feel better and that it is truly "fixed" now.

I am also still trying to convince myself to upgrade to Yosemite again. My brain tells me it should be no problem now... but my heart says "NOOOO! That's what started all the problems!" Which probably isn't actually true... I'm speculating (like so many others have done now) that there was a fundamental manufacturing problem with the graphics card that grew worse with time (heating...cooling...heating...cooling...), and which was finally pushed to the breaking point by the graphical demands of Yosemite. Now that the card has been "reflowed" it should not experience that "breaking point" again by Yosemite. At least that is what I hope.

So, anyone who is about to pull their hair out (as I was), and who has no warranty, and who lives 3+ hours from an Apple Store, might find some use from my experience.

I would also love to hear from anyone who has resolved your problem by baking and then installed Yosemite since that point. Have you been running Yosemite since then without any graphical problems or lockups? That would help me feel better to do so again myself.

And finally, thanks to everyone who posted your problems, thoughts, trial and errors, baking process, and solutions (and failures). It has all been invaluable to me as I have worked through my problems!

-Charlie

I also have a Late 2011 21" iMac with the graphics card pixel anomalies. They started showing up right after my apple care expired in early 2014. After first finding this board (and posting as iMattPro), I was able to get apple to run diagnostics and they found a fault on the thermal sensor on the graphics card. They were unable to reproduce the issue in the store (because it is warm in the store and in the testing area). They cleaned out my computer. My problem didn't go away and as the winter temps dropped my issue worsened. So, I decided to give applecare another call. To my surprise my initial contact send me up the ladder and I was able to take it back into the Apple Store. I showed them video of my graphic anomalies and this discussion where people were baking their video cards. After only about 20 minutes they agreed after manager approval to replace my graphics card (quoted at $175) for free. As it was at the store for repair this afternoon the store called and tried to say it was a chrome issue and I needed to do a clean install! He was simply unaware that my fix had been authorized and was "trying to save me money". After I explained the situation, he replaced my graphics card with no clean install necessary. I have had my mac back all evening and no graphics issues or pixel anomalies.

So, there you go. Thanks discussion board! Do not bake your graphics cards. Just be really nice but very insistent and have apple replace your video card.

Apple extended coverage on the 2011's due to a documented flaw some graphics card designs. You're not getting that with the 2010s.

They extended coverage for the 27 inch iMac only (because it was recalled) and that recall is now expired. I do not believe the late 21" iMac (at least from peaking over the genius' iPad) did not appear to have any such extensions for the graphics card.

It probably also doesn't hurt that this began right after your care expired and you had a history of them looking, mine waited until a full 2 years after Apple care expired. They had no interest in fixing it no matter how nice I was. Baking the card does work, and has been done with graphics cards outside of the Apple universe for quite some time. It also can fix broken XBOX 360s with some red rings of death. When all else fails you either have to spend money or bake your card. Try baking first.