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

Well, turns out this might be a hardware problem after all, since my iMac7,1 just locked up out of nowhere on 10.6.7 with 10.6.2 kexts.

Since this machine is more than 3 years old and waaay out of production, I guess I'm totally and utterly screwed.

****.

Not really what you can do is completely erase your hard disk and resinstall the OS that came with your computer and then upgrade to Leopard and Snow Leopard

Since I upgraded to Lion it didn't occured anymore on my iMac 8,1 (ATI 2600)

OS X 10.7.2 is out now

Try it out and let us know if your mac still freeze!

just upgraded. after reload i watched a flash video embedded in a web page --- result: GPU crash.

had to restore the good old 10.6.2 kexts.

i watched 10 other videos afterwards, everything is now fine. i can use iCloud now!

Hi All,

Sorry it's been a while, I was testing a new machine for this problem before posting the story of the old mac.

I encourage anyone with these issues to take your mac in for repair. I was covered by applecare, so that was lucky, but even if not, I would at least check it out.. So the machine (9,1 Lion stock ram NVIDIA GT 130), went in for a graphics card replacement as advised by the Genius at my local store, they had to order the part so took ages, replaced it and then said that they were having trouble during testing with some graphics distortion. Called me the next day and said the machine had passed and was ready for collection. Great! So I got it home and it was a brick! Wouldn't boot for crashing and then even stopped trying. So back to the store, Manager said sorry and that they were now "On it!", Hmmm. So they replaced the motherboard and the RAM.. Then I call to find out what's going on and they say that they can't get the machine repaired and they are going to replace it with a new 27" Base model... Great! So I don't get what was wrong if all major parts were replaced and nothing fixed it!! Anyway.. New machine had all my data put on it as was from the old 24" and it works like a dream, so obviously no data corruption either... Get those macs in for repair if you can. Many thanks

@swmaster: Just to be sure... it means that you can use the old 10.6.2 kext files on the new 10.7.2 without problems ?

yes, it seems so.

tried to stress-test it with youtube and various other embedded flash videos, and it's still OK.

ATIRadeonX2000 is from 10.7.2, the others from 10.6.2

crowley:~ bat$ kextstat | grep ATI

   83    2 0xffffff7f80ec6000 0x45000    0x45000    com.apple.kext.ATISupport (6.0.6) <76 9 8 7 5 4 3 1>

   84    0 0xffffff7f80f0b000 0xca000    0xca000    com.apple.kext.ATI2400Controller (6.0.6) <83 76 9 8 5 4 3 1>

   92    0 0xffffff7f81189000 0x261000   0x261000   com.apple.ATIRadeonX2000 (7.1.2) <77 76 9 7 6 5 4 3 1>

   97    0 0xffffff7f814b2000 0x12000    0x12000    com.apple.kext.ATIFramebuffer (6.0.6) <83 76 9 8 7 5 4 3 1>

Since some releases including Lion, I never have had those freezes anymore, even in tough situation like hot weather, video editing and so on...

However, (very) poor flash video performances were introduced by Lion. They are occuring after sleep, and are solved by a reboot. This is discussed elsewhere on this forum.

Finally replaced the problem office iMac with a new 27 incher and took the 24 inch in on its last day of Apple Care. They couldn't reproduce the problem, but swapped the video card anyway. No freezes for a month, but they returned last Friday and again today. Now I've got to transfer data back to the old mini the 24 inch replaced and bring it in again before the extended repair window expires.

Hey guys,

Due to this problem, I have abandoned working on the iMac, it is now unreliable. I really miss it though, and its powerful CPU.

Is there a way to remotely login to the iMac from another mac without causing the iMac's display to turn on? I think this will not trigger whatever it is that causes the freezing. Unfortunately I couldn't find a way to do it.

Any ideas?

Mota

Hmm, well this discussion seems to have been a bit mooted since 10.7.2 update, or is it just my imagination? I apparently have updated drivers 7.12.9 for my ATI 2600, running 64 bit for 8 days now. 8 days without a freeze. With Lion. Somewhat amazed. Not sure I dare shut down now. 

Well, I'm running a 20" iMac 7.1 and 10.7.2 still causes almost immediately freezes for me. However, if I apply the 10.6.2 then everything appears to work fine.

My personal feel on this as a software developer, is that it is a hardware or firmware errata which causes problems with the new drivers. When apple replace the GPU, they replace it with either a newer revision GPU, or a newer firmware, which makes the problem go away.

I'd be interested to see the "Revision ID" and "ROM Revision" from people here with affected 2400/2600 GPU's, and those with 2400/2600 GPU's that work OK. You can find this information in System Profiler, on the "Graphics/Displays" section

I'd like to add that the freeze ups also occur with NVIDIA GeForce 130 cards as well. I had mine replaced once but the problem persisted. Not until I sped up my internal fan using 'fancontrol' for Mac did my computer cool down enough to run without freezing. I know others have dismissed my theory of running a cooler temp CPU. But it worked for me. I can run flash now as well.