Red and green square dots?

5 days, still no issues, Bake-it!

Two weeks now and the spots came back.

I was watching a flash movie in Firefox and the vents of the CPU started spinning loudly, two minutes later the first squares reappeared. Flash in full screen grilled my GPU!! I'll send you a bill Adobe grrrr

Really? Correct me if I am wrong, but I think you are the first to have failure after baking. Is the problem the same as before or different? I think we baked around the same time, and I am still doing well.

The problem just started and has occurred twice in 10 hours and seems smaal at this moment. And it started with flash overheating mu GPU

Hello everyone,

We have two Imac 2010 mid with the same issu as everyone. As we knowledge apple doesn't respond to the problem. WE did send one imac to get check and apple said that everything was fine but the problem persist. I think it is time to take a lawsuit again the problem for the price we paid for our machine.

By the way we did the apple hardware test the long one and no problems came out. We do think that the problem is more software than hardware.

I've had this problem since december 2013, it's only getting worse. Next week I'm going to my Apple Service Provider to exchange the graphics card. I'm tired of this ****.

Well, it took 7 months after baking, but my dots finally came back.

I'm going to try round two of baking in a couple of weeks and will report back.

Cheers!

After much lurking, I'm about to bake my HD4850 following richlove's method (many thanks btw!). Just a couple of questiions:

- Should the card be placed with the chips up or down? (There does not seem to be a consensus about it)

- Some of the white puffy stuff remained on the memory modules after removing the heatsink. Should I remove the stuff before baking? If so, what product should I use to replace it?

Thanks!

I have a 2011 27 inch iMac with the same problem. I called the apple store and he had me do a key combination to reset the video on boot up.

He said the community was crazy for baking the video card and they will replace the video card at my expense if that didn't work.

He can thinks what he wants. All due respect but at the end of the day he's a step up from the best buy geek squad guys. And that's ok. There is actual science happening here, and this does work. This is not something unique to Apple. And infant these ATI Radon cards had similar issues in non-apple products.

Apple will replace the card at your cost. Ofcourse they will. But if you didn't have to pay apple to do it wouldn't you be better off? You can buy working graphics cards on eBay too. This is a last ditch effort before doing that.

I Got Apple to replace the card, as others have, and paid them to do it. That card simply went bad shortly after a period of time.

SInce the card is a Radeon, but uniquse to the iMac, it's not that easy to find, and I found cheaper to buy from Apple.

All that said, baking is the only thing that seems to work reliably, including getting Apple to replace it.

Cheers!

Here's a temporary fix that appears to work. I noticed that the dots show up big time when my imac goes into extended sleep mode. I would log in start working and within 2- 3 minutes everything would lock up forcing me to do a hard reboot and then everything would be fine or workable until the next time.

Suspecting it had something to do with automatic sleep mode - I now shut down running programs and then manually put the machine into sleep mode before I retire for the night. In the morning I usually have no issues as long as I stick to the routine and don't let it stay unused for any extended period of time which I am guessing is more than 2 or 3 hours.

Hope this helps as an alternative to baking.

The reason this happens is cooling. As the GPU cools very small gaps form in the solder. When it heats up it the solder expands and makes the gaps smaller. Baking reflows this and should re-fill the gaps. This will get progressively worse.

Hello all. I didn't scroll through all the pages of this thread, so perhaps the following detail has already been mentioned:

I mostly run using Win7 bootcamp on my Mid 2010 27" Mac. Recently, I switched to Yosemite 10.10.2 as the primary OS over Win7, and the screen problems appeared in force. When I go back to Win7, even for for a week or more, the problem goes away entirely. I don't have a single display issue while running Win7, and now I get constant display issues when running 10.10.2. There must be something in the way Windows uses the graphics card power management (either very efficiently, or very inefficiently) that keeps the problem from surfacing.

It's too bad, because I prefer the Mac interface, but it sound like short of baking the Graphics card, I may have to revert back to Win7 if things get worse.

Just a quick note to report that it's now been two weeks since I baked my GPU (200C, 7 minutes), and my iMac has been working fine since then.

Just one episode of screen-freezing-except-pointer, which of course I'm not sure if could be related to the cold solder issue.