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

Hello.


Got a brand new 27'' iMac, installed Lion. The machine freezes randomly when starting to play videos, either on Youtube, Quicktime, iTunes.


When it freezes, the mouse still works, but the machine doesn't respond to any command, requiring me to hit the power button and restart the computer.


Searched on kernel.log and system.log, and found no crash/error/message.


Anyone suffering from the same problem? The machine is pretty solid, been running some OpenCL kernels too and they are ok. It's only video decoding (possible on the GPU) that seems to freeze randomly.

iMac, Mac OS X (10.7)

Posted on Jul 21, 2011 6:46 AM

Reply
2,021 replies

Jul 23, 2011 1:30 AM in response to sdotb

@sdotb, Try every 30 minutes crash... check what's in your Startups and disable or remove them and also remove Applejack if you have that or any EFI type program (safety belt in the past).


Flush the PRAM, and SYSTEM OFF remove batt hold down start button and restart, go into recovery and run the stupid utility programs for repair, and if anyone knows path for maintenance in Terminal there I'd be appreciative.


Anyway, that and creating and USING a NEW Admin accont all have helped in specific and limited degrees.


I can't understand HOW apple could have such a great new-start with SNOW and fall on their face with this.


Their several advices to me is to UPGRADE, and I've heard that in the past when I only bought new systems... I've had over 40 Macs, and many loaners several new and several used... anytime a problem goes longer than their knowledgebase the reply always seems to be UPGRADE, buy more memory, or whatever ---- just BUY something it's your system it's not our fault we can do no wrong.

Jul 23, 2011 3:25 AM in response to rubenlx

Just to add my name to the list, I'm having the same problem. 27" iMac purchased early June, everything was fine until I install the Lion GM. Then, about once every three times I view a video, my entire Mac freezes. Audio continues, the cursor can be moved, and I get the following in Console:


7/23/11 12:02:40.000 PM kernel: ** Device in slot: SLOT--1 **

7/23/11 12:02:40.000 PM kernel: ** GPU Debug Info Start **

7/23/11 12:02:40.000 PM kernel: 0x00006740

7/23/11 12:02:40.000 PM kernel: 0x0000008f

7/23/11 12:02:40.000 PM kernel: 0x00000001

7/23/11 12:02:40.000 PM kernel: 0x00000018

7/23/11 12:02:40.000 PM kernel: 0x0000a880

7/23/11 12:02:40.000 PM kernel: 0x00000001

7/23/11 12:02:40.000 PM kernel: 0x00000001

7/23/11 12:02:40.000 PM kernel: 0x00006740

[continues for several hundred lines]


I first noticed this only when viewing videos in Safari, and thought it was a Flash problem. But today, after ripping a DVD with Handbrake, I went to QuickLook the file, and got the freeze. (It was an .m4v file.) So it's not Flash, but any video. I don't have this problem on my MacBook Air 2011, also running Lion.

Jul 23, 2011 3:32 AM in response to rubenlx

Just wanted to add my name to the list,


Also having the issue with my 27" iMac freezing. Honestly can't remember the 1st time it happened as wasn't expecting it, but the 2nd time was definately a flash issue. Was attempting to watch a Justin.tv stream and the whole computer locked up, only way to recover was to hard reset. Same as everyone else, mouse etc all functioned correctly but nothing else on the system would work.


Hope Apple releases a patch etc to take care of this, tempted to roll back to SL until the bugs are fixed.

Jul 23, 2011 5:21 AM in response to rubenlx

Similar topic here : https://discussions.apple.com/thread/3191134?answerId=15707339022#15707339022.


Most people report this on the 2011 27" imacs (radeon 6970m only ?). Problem seems to happen

when starting video when machine has been in standby mode.


I had screen sharing enabled, after disabling I didn't see the problem for almost 2 days.

I will re-enable it to see if I get the hang again.

Jul 23, 2011 6:33 AM in response to rubenlx

I have a 27" brand new IMAC. It is less then 2 weeks old. I moved to Lion and have the same issue. I just downloaded FIrefox and I am able to view flash videos from Youtube and Footytube. I try the same videos using Safari and it freezes. It is not just the Radeon 6970M, I have the folllowing.


AMD Radeon HD 6770M:


Chipset Model: AMD Radeon HD 6770M

Type: GPU

Bus: PCIe

PCIe Lane Width: x16

VRAM (Total): 512 MB

Vendor: ATI (0x1002)

Device ID: 0x6740

Revision ID: 0x0000

ROM Revision: 113-C0170F-170

EFI Driver Version: 01.00.544

Displays:

iMac:

Resolution: 2560 x 1440

Pixel Depth: 32-Bit Color (ARGB8888)




Like I said it is working when I use Firefox. I have not tried Chrome and probably won't.

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

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