Q: 24" iMac Screen Freezes since 10.6.3 update - pls help!

I have been using the original kext solution with success up until 10.8.3.  The original solution copies the 10.6.2 files ATI2400Controller.kext, ATIFramebuffer.kext, and ATISupport.txt into into /System/Library/Extensions.

Then did:

chown -R root /System/Library/Extensions/ATI*

xattr -src /System/Library/Extensions/ATI*

kextcache -system-prelinked-kernel

kextcache -system-caches

When I updated to 10.8.3, instant freezes, so I did the usual.  I got an error message this time about mach_kernel 32 architecture.. did not write it down though.. should have.  There are no hangs, but any moving video slows the system down to a crawl, so it is not even usable. 

Anyway, I have a 7,1 iMac with  the ATI Radeon HD 2400 XT 128 MB card, and wondered if others had issues with the kext solution in 10.8.3?  

Thanks!   Jeff

10.8.3 seems to be treating me right.  I've got 20" early 2008 with Mountain Lion, which I installed a few weeks ago. It's been freezing as described (movable mouse, but nothing else) at least once a day.  I was all set to fall back to the earlier kexts yesterday, then saw that it wanted to do the upgrade to 10.8.3, so I let that happen.  Before swapping out the kext files I checked to see if they were updated.  They were.  Decided to leave it alone to see if there was any improvement.  My system has been running smoothly since, and even seems faster. yay!

>find /System/Library/Extensions/ATIFrameBuffer.kext/ -type f | xargs ls -l

-rw-r--r--  1 root  wheel    2354 Mar 10 21:38 /System/Library/Extensions/ATIFrameBuffer.kext//Contents/Info.plist

-rwxr-xr-x  1 root  wheel  147280 Mar 11 17:20 /System/Library/Extensions/ATIFrameBuffer.kext//Contents/MacOS/AMDFramebuffer

-rw-r--r--  1 root  wheel     158 Mar 10 21:42 /System/Library/Extensions/ATIFrameBuffer.kext//Contents/_CodeSignature/CodeDir ectory

-rw-r--r--  1 root  wheel      80 Sep 10  2012 /System/Library/Extensions/ATIFrameBuffer.kext//Contents/_CodeSignature/CodeReq uirements

-rw-r--r--  1 root  wheel    1745 Mar 10 21:42 /System/Library/Extensions/ATIFrameBuffer.kext//Contents/_CodeSignature/CodeRes ources

-rw-r--r--  1 root  wheel    4064 Mar 10 21:42 /System/Library/Extensions/ATIFrameBuffer.kext//Contents/_CodeSignature/CodeSig nature

-rw-r--r--  1 root  wheel     466 Mar 10 21:41 /System/Library/Extensions/ATIFrameBuffer.kext//Contents/version.plist

>find /System/Library/Extensions/ATISupport.kext/ -type f | xargs ls -l

-rw-r--r--  1 root  wheel    2421 Mar 10 21:38 /System/Library/Extensions/ATISupport.kext//Contents/Info.plist

-rwxr-xr-x  1 root  wheel  500384 Mar 10 21:38 /System/Library/Extensions/ATISupport.kext//Contents/MacOS/AMDSupport

-rw-r--r--  1 root  wheel     154 Mar 10 21:42 /System/Library/Extensions/ATISupport.kext//Contents/_CodeSignature/CodeDirecto ry

-rw-r--r--  1 root  wheel      76 Sep 10  2012 /System/Library/Extensions/ATISupport.kext//Contents/_CodeSignature/CodeRequire ments

-rw-r--r--  1 root  wheel    1745 Mar 10 21:42 /System/Library/Extensions/ATISupport.kext//Contents/_CodeSignature/CodeResourc es

-rw-r--r--  1 root  wheel    4064 Mar 10 21:42 /System/Library/Extensions/ATISupport.kext//Contents/_CodeSignature/CodeSignatu re

-rw-r--r--  1 root  wheel     466 Mar 10 21:41 /System/Library/Extensions/ATISupport.kext//Contents/version.plist

find /System/Library/Extensions/ATI2600Controller.kext -type f | xargs ls -l

-rw-r--r--  1 root  wheel     4976 Mar 10 21:38 /System/Library/Extensions/ATI2600Controller.kext/Contents/Info.plist

-rwxr-xr-x  1 root  wheel  1856344 Mar 11 17:24 /System/Library/Extensions/ATI2600Controller.kext/Contents/MacOS/AMD2600Control ler

-rw-r--r--  1 root  wheel      161 Mar 10 21:42 /System/Library/Extensions/ATI2600Controller.kext/Contents/_CodeSignature/CodeD irectory

-rw-r--r--  1 root  wheel       80 Sep 10  2012 /System/Library/Extensions/ATI2600Controller.kext/Contents/_CodeSignature/CodeR equirements

-rw-r--r--  1 root  wheel     1745 Mar 10 21:42 /System/Library/Extensions/ATI2600Controller.kext/Contents/_CodeSignature/CodeR esources

-rw-r--r--  1 root  wheel     4064 Mar 10 21:42 /System/Library/Extensions/ATI2600Controller.kext/Contents/_CodeSignature/CodeS ignature

-rw-r--r--  1 root  wheel      466 Mar 10 21:41 /System/Library/Extensions/ATI2600Controller.kext/Contents/version.plist

Well, 1:20 after I posted this, it froze again.  Still, about 30 hrs is better than it had been.

Hello everybody. My machine with this video card

Jeu de composants :          ATI,RadeonHD2400

  Type :          Processeur graphique (GPU)

  Bus :          PCIe

  Longueur de la voie PCIe :          x16

  VRAM (totale) :          128 Mo

  Fournisseur :          ATI (0x1002)

  Identifiant du périphérique :          0x94c8

  Identifiant de révision :          0x0000

  Révision de la ROM :          113-B2250A-207

  Version du gestionnaire EFI :          01.00.207

Is running faster and stable from now several days. Kext applied with combo download.There is only one exception : when running a virtual machine (Windows) with VMWare Fusion, system freeze or slow down dramaticaly. Any idea is welcome.

Regards.

@joel387

It seems some have better results (running smooth for more than 10 days) using the combo update.

Maybe you could try applying the combo 10.8.3 update?

Please share your findings.

Sorry my previous message was wrong. I updated my machine with combo update and I DO NOT apply kext fix.

Update with apple store for me do not solved the problem. Update with combo seems to solve it.

Sorry for confudion.

Jeff,

I have the same Mac, same ATI Radeon HD 2400 XT 128 MB card. Updated to 10.8.3 via combo update. Worked for about 1.5 hrs. Then froze. Subsequent restarts even froze the mouse. Continued to try to restart. Eventually started. I had kext fix files in a folder on my desktop for just this emergency. Quickly ran it … All is OK one week later.

It appeaers that for some with ATI 2600 combo update works but for ATI 2400 not so much.

Suggest you use Flash Disk or DVD copy Mountain Lion and Time Machine to revert to an earlier system. Copy the kext files to your desktop. Try combo update again. You will have problems getting it to do a stable restart but it will for a while. It finally did for me. Then quickly run kext fix.

Must Include:

ATIFramebuffer.kext

ATISupport.kext

As well as controller. kext files

Bob

Is your Combo download AFTER 15 of March ?

Regards

No! I downloaded on 13 March.

Bob

I'm not sure if I did the combo update or not. 

Software  OS X 10.8.3 (12D78)

But I'm pretty sure it was the same list of fixes:

About OS X Mountain Lion Update v10.8.3 (Combo)

The 10.8.3 update is recommended for all OS X Mountain Lion users and includes features and fixes that improve the stability, compatibility, and security of your Mac, including the following:

• The ability to redeem iTunes gift cards in the Mac App Store using your Mac's built-in camera
• Boot Camp support for installing Windows 8
• Boot Camp support for Macs with a 3TB hard drive
• A fix for an issue that could cause a file URL to quit apps unexpectedly
• A fix for an issue that may cause Logic Pro to become unresponsive when using certain plug-ins

     A fix for an issue that may cause audio to stutter on 2011 iMacs

• Includes Safari 6.0.3

In any event, it's been up for 26 hours now.

The combo I used was published on 14th March ! And I verified yesterday, the 3 kext related to ATI 2450 card are dated 15th of March !!!!! How is it possible ?

Can you control the date of your 3 kext files ?

It appears that some logging in here are new, and have not heard of Krysztof Turek's kext fix for this problem. His fix is for ATI cards in older iMacs. After 10.6.3 (2009) these Macs have been crashing. My understanding is that it has something to do with some dispute between ATI and Apple. Anyhow Apple keeps trying to rewrite drivers for the cards and they don't work. We have to go back to the drivers pre-10.6.3. This brilliant Krysztof Turek came up with this fix that reinstalls the older drivers. Nearly every upgrade since 10.6.3 has needed this fix because apple upgrades overwrite them. The files are dated Aug 3, 2009.

I can't find the source of the files anymore. I downloaded them a while back and stored them in my desktop.

Directions are on Krysztof Turek's blog at:  http://blog.krzysztof-turek.com/apple-imac-8-1-freeze-problem-solution-en/

I zipped and placed all the files and the install app on my public Dropbox. Anyone can download it here: (hope this works!)

https://dl.dropbox.com/u/90315541/Krysztof%20Turek%27s%20Fix.zip

Good luck

Bob

Today 26-03-2013 20.50 I updated to 10.8.3 with the combo update.

Did not apply kext fix yet.

Computer:

iMac 8.1 24"

ATI Radeon HD2600Pro 256MB

Lets hope Apple realy fixet the problem.

Where would I find the kext fix?

27 inch iMac Mid 2011

@nuvest7

This discussion is largely about the iMacs 8.1 with the ATI Radeo HD2600 pro an 2400 from 2008/2009.

I think your problem is different.