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

I don't know if this is just coincidence or not, but since updating my iMac to 10.6.3 it keeps on crashing. On 3 separate occasions today, whilst using my Mac the screen has gone completely black with thin white lines down it.....see pic below:

http://picasaweb.google.com/lh/photo/6SYzhCgVYEU5TBKqRfOQ1Q?feat=directlink

The fans and hard disk are still running but it will not respond to any keyboard or mouse presses - I simply have to turn it off by holding the power button in.
It will then restart as usual.

Anyone got any ideas? Do you think that if I was to re-install Mac OS X from my original install disk it could solve the issue?

Thanks

Darren

24" intel imac 2.8Ghz, Mac OS X (10.6.3)

Posted on Mar 31, 2010 2:43 PM

Reply
1,804 replies

Jan 10, 2013 12:15 AM in response to DazzaG

Just jumping on this as my 2007 24" iMac has started to freeze and "GPU Debug Info End" with a load of kernel[0] entries are newcomers to the system log. Have noticed the whole GPU area has started to get hot (60ºC) and warm up with literally no activity. Can't see GPU activity as it seems to have been blocked from the 3rd-party monitors in 10.8

Jan 10, 2013 4:20 AM in response to McDave

And if the problem was linked to the kexts inducing hardware problem, because of the controller heating more for example ?


Look at this : #451: someone managed to repair an Apple motherboard by resoldering a BGA (Ball grid array) chip.


Somebody feels like trying this ?


My iMac 8,1 with the ATi 2600 has exhibited very exactly the symptom described here some years ago but inexplicably healed himself after five or six crashes. Today I'm using the stock kext that are loaded with ML 10.8.2. As an electronician, it makes me believe that is hardware related (but software induced).

Jan 10, 2013 5:59 AM in response to Pagaille

You're all getting too technical for me! I don't know what kexts are, but am still getting the freezing. It seems random. Sometimes it goes for several hours ok, with maybe one freeze, then next day it will freeze 5 or 6 times. Firefox or Chrome -doesn't seem to matter. The on/off button is getting a LOT of action....😟...and what on earth is a "kernel panic" ?

Jan 10, 2013 6:48 AM in response to Soul Nut

Kexts stands for Kernel Extension. Kernel extensions are little pieces of code that are needed for various hardware and software to run in OS X on your Mac. There is an extensions folder located in OS X system folder where kexts reside. The kext file everyone is talking about is a kext driver code fix for the iMac's video card. I haven't read this whole topic here, but the kext file seems to be specific to a certain video card model. But then, I am not completely sure of this. The kext file fix needs to be downloaded and the file placed or replaced in OS X system>library>extensions folder for the file to work.

A Kernel Panic or KP is a situation where OS X base Unix code called a "kernel" finds either a hardware or software issue that it can't resolve that results in a freeze or "panic" of the basic Unix software code.

If your iMac is experiencing KPs, it could be related to the problems you are having.

Feb 1, 2013 2:21 AM in response to KrzysiuTurek

Hello KrzusiuTurek and everybody,


great great great work around !!!!!

Thank you so much. Working fine for me : fresh installation of OS X.8.2, 3 kext replaced with 10.6.2 version and the machine is now stable.


I have 2 identical machines : same model, same graphic card (HD 2400 XT), same ROM, same EFI version, ...

One is running 10.6.8 without any problem.

The second one freeze every 3 minutes with : 10.6.6, 10.6.8, 10.8.2, ... Now installed with 10.8.2 and 3 kext from 10.6.2.


Why this difference between the two maxhines ? I don't know. Any idea ?


iMac 20" with following graphics card

ATI Radeon HD 2400 XT :

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 ** périphérique : 0x94c8

Identifiant de révision : 0x0000

Révision de la ROM : 113-B2250A-207

Version ** gestionnaire EFI : 01.00.207

Moniteurs :

iMac :

Résolution : 1680 x 1050

Profondeur de pixels : Couleurs 32 bits (ARGB8888)

Mar 5, 2013 12:36 AM in response to DazzaG

Hi,

what about 10.8.3 beta ?


Does it change antything about this freezing problem. I have just had a freeze which is related to the GPU. My GPU is brand new - a replacement for GS 8800.

I cannot belive that is was not fixed since 10.6.3 !!!!

Mar 15, 2013 10:39 AM in response to Community User

indeed, it does.


2400 was version 8.0.61, became version 8.10.44.


-rwxr-xr-x 1 root wheel 343848 Sep 11 2012 AMD2400Controller

new:

-rwxr-xr-x 1 root wheel 1856224 Mar 12 01:24 AMD2400Controller


same goes for 2600.


old:

-rwxr-xr-x 1 root wheel 343976 Sep 11 2012 AMD2600Controller

new:

-rwxr-xr-x 1 root wheel 1856344 Mar 12 01:24 AMD2600Controller


way bigger, folks. had no chance to upgrade my imac7,1 but will report as i'm done.

Mar 16, 2013 1:46 AM in response to DazzaG

So the questions are again:


* Does the ML 10.8.3 update fix the freeze problem with the 24" 8.1 radeon HD 2600 pro and HD 2400

(Every time I installed a ML update the first couple of hours/days it seemed like it was fixed, but the freeze problem always returend and I had to apply the kext fix again!)


* If the 10.8.3 update did not fix the freeze problem, does the kext fix still work?


Hope to hear some reactions soon.

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

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