Mid 2011 iMac Graphics Problems with Yosemite

K_Rek solution didn't work for me. It keeps rebooting after replaced the AMD6000Controller with the Mavericks version.

I have the iMac 27 inch mid 2007 model, with the (AMD) ATI Radeon HD 4850 512 MB graphics card, which is having issues.

When running Lion and Mountain Lion, the only way to get it to work was boot into safe mode, backup and remove all of the AMDRadeonX* and ATI RadeonX* kexts and driver bundles as well as the AMDRadeonVADriver.bundle from /System/Library/Extensions, then reboot.

This gives you a "working" machine, but without the Quartz Extreme graphics capabilities. I have been running like this for about 4 years now.

I have found with Yosemite that I can no longer use the Chrome browser, due to constant refreshes within the page, but both Firefox and Safari seem to be OK. I was getting by with an older version of Skype that allowed my iSight camera to display, but that no longer works, I can't see the person I am talking to.

There are a few other tweaks, fixes and compromises, but I should eventually work them out.

Annoyed that the Stocks notification does not recognise Mutual Fund symbols...

I think I fixed graphics issue.

(My case was green and purple tiny square dot, freeze, slowness and cannot find correct resolution for second display)

My imac is mid 2010 27" core i7 iMac with ATI Radeon HD 5750 with 1 GB of GDDR5 SDRAM model.

Here is what I did.

Since my graphics card is AMD 5xxx series I renamed /System/Library/Extensions/AMD5000Controller.kext to some other name.

(like AMD5000Controller.kext.org)

for 2011 imac driver will be AMD6000Controller.kext

Then I copied same driver from Maverick backup.

reboot imac. wait for system to boot up.

However, I have got system error. and my imac went into infinite loop of boot up system.

so that basically my mac is no longer boot up (sound pretty bad isn't it? but don't worry)

after watching retrying boot process (I don't know if its necessary) then press the power button to shutdown.

now trying to boot mac with safe mode.(regular safe mode boot procedure)

In order to do so I connected usb keyboard. (wireless keyboard didn't work)

press the power button, immediately after you hear the startup sound, press and hold the shift key.

Release the shift key when you see Apple logo.

Then after system come up log on to your account, navigate you to /System/Library/Extensions folder.

remove bad AMD5000Controller.kext then put backed up driver to AMD5000Controller.kext

(This case I backed up original one as AMD5000Controller.kext.org)

Then reboot one more time, system boot up correctly and problem is gone.

now no more noisy pattern, no slowness, second display works as it should be.

I've been testing my mac over 6hrs now with video playback, photo edit, video encoding.(many many CPU/GPU intense task)

but all working fine now.

I convinced Yosemite's graphics driver itself is good. The problem is some broken or incompatible preference/config/setting file for graphics card is left on the system drive somewhere during migration.

This procedure may remove or reset such files.

I hope this will help you.

PS

if you do not have Maverick copy of AMD?000Controller.kext, try just copy bogus driver as AMD?000Controller.kext or may be

simply rename original driver to something else (with different extension other than kext) and restart may work.

(of course you need to fail boot up once and go into safe mode to fix it)

I'm having graphical problems like lag when I move windows on my iMac (27", mid 2011).

I have the ATI Radeon HD6970M (2 GB) graphics card.

It has to be OS X Yosemite's problem because everything works fine with OS X Mavericks.

And it's not a hardware problem, my iMac has good specs.

The machine has an Intel Core i7 with 16 GB of 1333 MHz DDR3 RAM.

I don't know how related this is or not, but it seems like these graphical issues are all over the place on Radeon hardware. I'm having horrible lag when triggering Mission Control and in Java (imageJ) on my Late 2011 Mac Mini. Late 2011 Mac Mini slow video refresh on Yosemite

When java tries to draw/refresh it's like downloading a JPG over a 28.8 kbps connection, when last week on Mavericks it was totally fine.

Same color square block here... Always after computer went to sleep. More color square when I'm in mail app... They disappear after 1 or 2 minute, only come back if the computer go to sleep. No problem with Maverick!

Imac 27" mid-2010

ATI Radeon HD 5750 1024Mo

I've been having the same video corruption problems since upgrading to Yosemite (iMac mid 2011/AMD Radeon HD 6970M): strange (beautiful!) patterns on the screen, can move the mouse but can't interact with computer; restart doesn't complete...

I called Apple and the rep made me go through these steps and so far so good:

Empty the content of these folders (not the folder themselves):

• Macintosh HD/Library/Caches
• Macintosh HD/Library/LaunchAgents
• Macintosh HD/Library/LaunchDaemons
• Macintosh HD/Library/StartupItems
• Macintosh HD/Users/[your home folder]/Library/Caches
• Macintosh HD/Users/[your home folder]/Library/LaunchAgents

Restart, log in, try to empty the trash... I will comment again if problems come back.

Hi Everyone,

I have experienced the very same issue with an 27" iMac mid 2011 (AMD Radeon HD 6770M 512 MB).

I cleaned all Caches and StartupItems as suggested by Jean-Michel. Let's see if that helps the issue..... (btw. I experienced extremely poor performance while running any Windows version in VMware Fusion since migrating.... but that's probably not related).

Now let's see how long Yosemite stays up and running....

Günther

Hi all,

I have the same issue with my 27" iMac Mid 2010 ATI Radeon HD 5750 1024 MB.

I've also just cleaned all folders as per Jean-Michel Dentand. I notice my iMac lost it's record of backups to Time Machine but that's not a big one to overcome.

So far so good - no corrupt graphics blocks :-)

Will reply if I do get them again.

Levimor

Did they explain why that might help at all? All I've got in those folders are what look like things that start up upon boot and I don't understand why those would affect your graphics card performance.

Unfortunately I have just now seen the colored square block errors again.... system didn't crash yet (it only does at times). @bhive01: can't tell, but obviously cleaning out everything not part of the OS itself could be a potential issue. At this point I still guess this is a graphics driver issue and to be solved by an update to the ATI Radeon driver...

Yeah, I think this is a distraction from the fact that they half-assed the drivers. My same age MBA has better performance than my mac Mini because it's using integrated graphics. The multitude of issues I see on these forums are only because of discrete chips.

Ever since moving to Yosemite, I have the exact same problem on my MacBook Pro 17" Late 2011. 2.5 GHz Intel Core i7

For some reason it's happening more than ever before.

Here are my own observations:

1. I noticed my fan has been very quiet lately, and that these problems are somehow triggered by heat issues, because I only see the problem when I run a lot of things at once, or I'm doing something graphics intensive such as video / photo editing or streaming video. These activities usually trigger faster, much louder fan sounds. However, in spite of the activity... the fan is still super quiet.

2. Since I was curious about the lack of fan noise, I opened up the case and saw the fans running... quietly, so I know they work, but somehow they are not being told to increase the RPM because of the extra activity / heat.

3. Based on that assumption, I located a free monitoring program on MacUpdate that let me see my CPU temperature and fan RPM in real time. As such, I let my MacBook cool off, then checked the temperature as I did some graphics... the CPU reached 140 degrees F, but the fan remained at 2000 (the default). At this point the system started to show all the signs in this thread... and it soon crashed.

4. Next, instead of just using the program as a monitor, I set up a profile called Max... where I cranked up the RPMs to over 6000... and I was happy to hear the familiar sound of my CPU Fans, which I hadn't heard in quite a while and as I type this, my temperature has remained rock solid at 91 degrees F... No crashes or artifacts so far.

Also... When I look at "About This Mac", it reports "Intel HD Graphics 3000 512 MB", and does not mention the AMD Radeon unless you look at the system info section. To be honest, I'm not sure if it used to be on the front page, but it does seem odd that it's not mentioned.

My next test will be to try cranking out some high intensity programs, to see if the CPU gets into the danger zone.