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

Hi MDS,

I agree that this thread is confusing, but as I said, I have persevered and all appears fine now - worked for 8 days without incident, then shutdown for 6 days, now running for 11 days without any trouble. (quite unbelieveable…). So I would give 10.7.2 a go, making sure that you are in 64 bit kernel mode (and use time machine).

If it fails exactly as before then that would be a real headache, but I would still try the 10.6.2 kext fix as that worked for me under 10.7 and 10.7.1. Again 64 bit mode and kext helper (note that kext helper also froze for me whenever I did this fix, requiring a hard shutdown, but the kexts were installed fine.)

And just in case my bug report had any effect whatsoever, I would report your bugs to the developer forum if you are a member (I am registered but not enrolled - that is only a non paying member:  http://developer.apple.com/support/resources/bug-reporting.html - I included a dump from the console when it registered a GPU crash, but it wasn't so obvious under the Lion version of console and I never went any further with it. I understand that Apple only host the discussions threads, they do not undertake to read or respond to them so you need another "in" if they are to see this. No guarantees unless you have Applecare!! (but there is at least one youtube clip of how to complain successfully to Apple on the phone...)

Thanks for the reply Simon. I gave up and am in the process of restoring 10.6.2. I need my machine to work. It's a production machine and I just don't have time to fool with it anymore.

Also, I'm not really sure what booting in 64 bit mode is. Isn't Lion only 64 Bit? Also, another poster said the following:

"Don't replace the Lion drivers on your model iMac.

You will get a kernel panic when booting if you do and you will have to reinstall the OS back to factory settings."

He stated that the 10.6.2 kext files are 32 bit.

I guess that's where all of my confusion comes in. Just too much I don't understand and not enough time to thoroughly research it.

Thanks again for the response.

For people with a 7.1 iMac, as I stated in an earlier reply Lion does work with the 10.6.2 kexts:

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

                                                Oct 21, 2011 7:20 AM                                                    (in response to Brian from VA)                                                               

Here is the info for my affected iMac 7.1:

ATI Radeon HD 2400 XT:

Chipset Model:    ATI,RadeonHD2400

Revision ID:    0x0000

ROM Revision:    113-B2250A-207

Working fine with Lion 10.7.2 and kext 10.6.2.

Simon Baker,

Are you still running without freezes?  I'm about ready to take the plunge into Lion.

Thanks!

Ooops, as for above, I just read your 11-9 post.  Thanks.

Thanks. I guess I'll give it a try. At this point, why not. I'm working mostly full-time on my MacBook Pro which is running Lion fantastic.

Just one question that I'm still confused on...

What is booting up in 64 bit mean? I'm not finding what that means or what I'm supposed to do.

Richard.... are you booting anyway special or just booting into Lion as always?

Let me know if you can.

Thanks.

As far as I know, it is not possible to boot a 7.1 iMac into 64-bit mode. So, no, I'm not doing anything special, just installing the 10.6.2 kext files.

Thanks Richard. I appreciate you answering so quickly. I plan on giving the 10.6.2. kext files a shot soon. Of course, now I've been on the imac all day today without a freeze. Never know when it's going to happen. I will certainly report back here what I encounter.

I'm having the same issues.  I reported them on the report link.  As luck would have it, I have Apple Care on my early 2008 3.06 24" iMac until November 27 (talk about nick of time!), so I'm taking it to the Apple Store Sunday to sort out.  If there is any issue with the hardware (this one has the NVIDIA GeForce 8800 GS), at the very least I will have documented the problem prior to the expiration of the Apple Care plan.  If not, hopefully they can help sort it out.

This started recently, my guess is following the 10.6.8 update.  I'll discuss upgrading to Lion with them, but I also referenced this thread when I set the appointment.  Hopefully I'll get it sorted out.

After lagging along the last few days my imac froze a couple of times today. So, I finally bit the bullet and installed my 10.6.2 kext files as Richard stated above. No problems so far. Booted right up and the computer seems to have the old response that it had prior to the update. So, I can also confirm that running the 10.6.2 kext files do work in Lion 10.7.2.

Now, with that being said, I've only been working for about an hour. I will report back in the next few days to let everyone know what's going on. My main question is why hasn't apple just reverted back to the 10.6.2 kext files for this setup? Do the newer version work on some machines and not others? Would love to know. But for now, I'll ride it out for a while. I'm including a snapshot of my Mac specs for anyone who wants to compare. I believe they are the same as Richards as mentioned a few posts up.

I have the exact same machine.  Just tried the 10.6.2 files again, but no luck.  Still same display freeze mid-animation (coming out of mission control).  Sometimes it will work for a while but usually freezes pretty quickly if using mission control.

http://db.tt/sFatZG9Z

Never tried mission control before. So, just launched it a bunch of times. So far, so good. Of course, now it's been just over two hours.....

I'll report back at the end of the week. See where I'm at then.

hey there.

let's make it clear: the 10.6.2 drivers ARE 64 bit. better said 32/64 bit, depending your booted kernel.

i don't know, how did you copy the 10.6.2 kexts and exactly what files did you copy over to /S/L/E

before trying to use some heavy gfx intensive stuff (mission control, safari with embedded videos, etc),

just open up a terminal window, and type the following magic commands and post us the results so we

can make sure you are really running the wanted version kexts:

iMac:~ user$ kextstat | grep ATI

you shall see something similar:

   81    2 0xffffff7f80ebf000 0x45000    0x45000    com.apple.kext.ATISupport (6.0.6) <74 9 8 7 5 4 3 1>

   82    0 0xffffff7f80f04000 0xca000    0xca000    com.apple.kext.ATI2400Controller (6.0.6) <81 74 9 8 5 4 3 1>

   92    0 0xffffff7f81189000 0x261000   0x261000   com.apple.ATIRadeonX2000 (7.1.2) <75 74 9 7 6 5 4 3 1>

   97    0 0xffffff7f814b2000 0x12000    0x12000    com.apple.kext.ATIFramebuffer (6.0.6) <81 74 9 8 7 5 4 3 1>

with exception of ATIRadeonX2000 (ver. 7.1.2) all the others came from 10.6.2.

just to be sure: if you copy over the files to /S/L/E, no matter how you do it, osx rebuilds the kernel caches. one has to wait couple of seconds (maybe minutes) to make sure, those caches are really rebuilt.

osx refuses to load kexts, which are not owned by user root & group wheel, and shall not have extended attributes (can be checked with ls -l@).

basically this two failure scenarios can be avoided by fixing permissions (which takes time up to 2-3 minutes) or by issuing this commands in terminal:

sudo chown -R root:wheel /System/Library/Extensions/ATI*

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

but first, just send in the kextstat output. in case you need i can provide you the kexts.

Hey swmaster,

Thanks for the reply.  I'm pretty sure I've got the right files and have them installed properly.  Not sure about the waiting thing; I probably rebooted within 1 minute after installing the new files:

MrFreeze:bsm johnk$ kextstat |grep ATI

   70    2 0xffffff7f813f1000 0x45000    0x45000    com.apple.kext.ATISupport (6.0.6) <69 9 8 7 5 4 3 1>

   71    0 0xffffff7f8173b000 0xca000    0xca000    com.apple.kext.ATI2600Controller (6.0.6) <70 69 9 8 5 4 3 1>

   73    0 0xffffff7f81436000 0x261000   0x261000   com.apple.ATIRadeonX2000 (7.1.2) <72 69 9 7 6 5 4 3 1>

   76    0 0xffffff7f81724000 0x12000    0x12000    com.apple.kext.ATIFramebuffer (6.0.6) <70 69 9 8 7 5 4 3 1>

I used kext helper 0.7 to install them

MrFreeze:bsm johnk$ cd /System/Library/Extensions/

MrFreeze:Extensions johnk$ ls -l@|grep -i ati

drwxr-xr-x  3 root  wheel  102 Nov 15 14:58 ATI2600Controller.kext

drwxr-xr-x  3 root  wheel  102 Nov 15 14:58 ATIFramebuffer.kext

drwxr-xr-x  3 root  wheel  102 Nov 15 14:58 ATISupport.kext

Thanks for checking these.

Same computer, same issue. Just had the logic board, video card and a few other things replaced and it is freezing completely, while the mouse still works (well, it moves anyways). Prior to having all those things replaced, it was still freezing quite regularly.

2008 iMac 24"

2.8 GHz Intel Core 2 Duo

4GB 800 DDR2

ATI 2600 Po 256

OSX Lion 10.7.2