Q: OSX Lion + 2011 iMac 27'' + Video = Freeze

Close to 100 pages and still no fix :-(

My iMac 24" early 2009 (under Lion) freezes on a regular basis especially if there are graphic intensive tasks. It never froze under Leopard or SL. I brought my iMac to an Apple Store but they were completely clueless. Ironically, I chose to not upgrade my MacMini1,1 to Lion and it works like a charm.

Starting to loose my faith in Apple and its customer service.

Yeah, I had a trusted workhorse iMac/Leopard since 2008.. Never skipped a beat (unless you want to count a defective dvd/cd drive that went bad.) 

I expect a glitch or two... but NOT one that litterally has run on this long without hearing one peep from Apple. 

I wonder if Siri knows the answer..

literally.. 

DON'T tell me my spell check is BROKEN TOO

LOL!

I submitted three panics to Apple this weekend. This morning the errors look a little different. There's the GPUrestart and the 'NVDA(OpenGL): Channel exception! exception type = 0xd = GR: SW Notify Error', but, before that, there are a lot of firewall errors. This is during start up. Anybody seen something similar?

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It really saddens me (I wrote "s u c k s" and they censored it) that Apple is not responding to this thread...

I have the same problem and there doesn't seem to be a cure.

Help, anyone?

I've not read all 99 pages of this thread but am having the same (or similar) issue.

Just one question (which may have already been answered) When your system freezes, can you unfreeze it by swiping to another space and back using the magic mouse? The works for me (temporarily)

I have had the same freeze problems as many of you, but they have now been fixed = hardware failure. I hope my frustrating story can be of help.

Bought my mid 2011 21.5" iMac (1TB) with Snow Leopard in mid September 2011.

Rather directly it begun to freeze randomly. When freezing, the mouse pointer could sometimes be moved, sometimes not. Inno cases did anything happen when I tried to click. Music could continue to be played. It was not possible to shut down any other way than doing a "hard"shut down. Sometimes thefreeze occured after waking up the Mac, sometimes directly after boot.And sometimes when opening an application such as Safari. Simultaneously with the freeze, I got a lot of "odd" messages in the log, including about kernal panics.

Did allthe things and tests you're supposed to do (including disconnecting from USBhubs, deinstalling non-Apple software, run the hardwaretest a couple of times, which did not indicate any problems); nothing helped. Tried some tips and work-arounds suggested on vRious forums on the web. Nothing helped.

First contact with Applecare resulted in reinstalling Snow Leopard (and theby overwriting the hard disch with 000000...)= first reinstallment. problems remained.

Second contact with Applecare resulted in handing in the Mac to hardware support. Theydid not detect any hardware problems, but noted the freeze problems. They reinstalled Snow Leopard = second reinstallent, and thereafter did not note any freeze problems; problems solved they claimed.

At home, the same freeze problems continued.

Installed Lion = third reinstallment, and did notconnect anything via USBhubs, nor did I install any software etc and did not upload photos etc = the Mac wasabsolutely "clean". Problems remained.

Third contact with Applecare resulted in reinstalling Lion = fourth reinstallment (and again overwriting the hard disc with 000000... And not connecting anything, not uploading anything, not installing anything else). Problems remained.

Fourth contact with Applecare resulted in handing in the Mac for hardware support. This time - as advised by Applecare - toanother shop. Same as last time and anew reinstallment of Lion= fifth reinstallment. They thereafter did not experienced any freezematters. Problems solved they claimed.

At home again, the problems continued....

Fifth contact withApplecare resulted in handling in theMac forhardware support again. And forcing the shop totalkwith the Applecare guy. A new logic card was installed. Random freezes continued. The old logic card was reinstalled. A new grafic card was installed. And suddenly the problems disappeared.

At home (last week), the computer as now run as it should for a week. Everything is installed on it, plugged in into the USB hubs, been uploaded etc, and everything works (i.e. For the first time since mid September 2011).

Conclusion: the freeze issues turned out to be related to a defectice grafic card. At no time did Apple's hardware tests indicate hardware problems (neither when runned by me, nor when run by the pros). The "odd" messages in the log apparently did not help the pros (neither Applecare, nor the two Apple authorised shops I did frequent) to indicate what was wrong. The defective card was detectedby trial and error.

I don'tnow if tdhe freeze problems can be assumed to be grafic card related in general, but it is my advice to have the card checked in case of random freeze problems.

Very strange solution for me. I posted earlier, regarding an iMac 5,1 clean install of Lion with nothing else installed and no peripherals.  Sometimes only seconds after a cold boot, I would get the freeze.  As with most of the other reports here, the mouse pointer would move but otherwise the system was unresponsive. 

After reading through many of the posts here, I remembered that one of my customers had a very similar crash on his iMac, that I was able to resolve by simply CHANGING the Screensaver settings. Out of desperation, I gave it a go, and now I'm on my 4th day without any crashes. 

In this case, "use random screensaver" was checked, so I unchecked it, and selected "Forest" which seemed pretty benign. In my customer's case, I recall the offender was a screensaver that accessed the internet, but I don't remember exactly which one.

Maybe this will help someone else...

I bought my 27" in June 2011, a fully decked out i7 QuadCore with a totally different graphics card. 530m: Your computer uses the AMD 6770 with 512 of DDR5 memory and my returned iMac was using the AMD 6970 with 2Gig of DDR5 memory, so it would be interesting to see if some how the updates are causing the graphics cards and other hardware to fail. I basically gave up after 3 so called fixes and asked for store credit and I ended up getting a Macbook Pro for my wife, a decked out Mac Mini and the Thunderbolt display for now. I am hopeful that I can get another decked out iMac in the future, I think with this many complaints they need dig into resolving these issues before my confidence is back.

Fustbariclation: Interesting to see all the Kernal panics as I got similar ones as well, and it looks like there could be an issue with your graphics card as well based off of that infomation I am seeing from your post.

Very interesting:

http://highmac.com/how-to/fix-kernel-nvdaopengl-channel-exception/

https://discussions.apple.com/thread/1916253?start=375&tstart=0

There's no way it can be JUST the graphics card.  It has to be the graphics card AND something else, at least.  It doesn't just affect new Macs, but old ones as well.  It could be a software update that's incompatible and is basically burning out the hardware.  But suddenly this started happening out of the blue, with new Macs and old ones (mine is from 2007), so there has to be a reason beyond a defective graphics card.

I'm also curious to know how many people are running Time Machine.  I seem to notice that I get some spotty mouse action/freezing when TM is doing an update.  But I don't know if it's the spinning clock that's making the graphics card to haywire, or the update itself. 

In any case, my iMac was rendered pretty much useless earlier today.  I have had two shutdowns that the OS itself initiated.  I saved those crash reports if anyone wants me to post them here.

Curious to know - which OS came on the MBP and the Mini?

Running SL made the top of my iMac really hot (like it was overworked..)  When I ran Leopard on the 2nd partition, that didn't happen..

I am in the process right now of erasing my entire HD and going to put Leopard back on there, then wipe the external HD and start over.  I have Time Machine, SuperDuper, iDisk and Carbonite... SURELY ONE of those will help me get just my files back.  LOL!

Good luck with your new equipment! 

My MBP came with Snow SL loaded and then I updated it to Lion, everything seems to work fine so far, which is ironic. My Mac Mini, just arrived today and I not sure what I will do as my TM backup is saved off of my iMac which was running SL. Frankly Leopard was one of the most Rock Solid OS on any computer, SL wasn't bad till they got to some specific updates thats when things started getting bad, and that does for Lion as well. I am hopefully Lion will pan out and become decent, but that remains to be seen. I Would try a 3rd party Ap called SMC control as even the Apple Care guys use it.  Good luck, as I have done the same before as far as rebuilding goes, ironically since 2003 I haven't had any hardware or software issues.

It is the strangest thing.. that just some of the computers will accept SL and L, and some don't.  Of course if people aren't having issues, they aren't going to come here... so it seems like everyone is having problems, and we know that's not the case.

It's got to be a 3rd party software issue.. but then again, why would SL cause my machine to run hot, and not Leop?  Graphics card not big enough?  I'm SURE I would love SL or L..  But in my line of work, I have to use old programs that offer no compatibiity (at this point.)  So I'm stuck for now.  Leopard is a work horse.

I am just sooo thankful that there are people on here that are willing to help!  This isn't nice, but it's comforting to know I'm not the only one with "issues."

I'll look into the fan control, if it gets hot again..  Thanks for the tip!

Just  FYI to those thinking from going to Lion to SL, it can be done. I am going to attempt this with my new Mac Mini I just received and a friend of mine who just bought a new Mac with Lion on it went back to SL. I might see what this thing can do with Lion first and if I have issues I will go back..

http://www.redmondpie.com/how-to-downgrade-os-x-lion-to-snow-leopard-the-complet e-tutorial/

What is the problem?