Mountain Lion freezes on MacBook Pro

What exactly happens when it freezes, and how do you recover?

I also have the same problem, i though that it was a failing hhd, but i replaced it, did a clean install and it freezes, but sometimes not just with google chrome but also with itunes being the only app open. macbook pro 4,1 running mountain lion 10.8.2

The next time you have the problem, note the exact time: hour, minute, second.

If you have more than one user account, these instructions must be carried out as an administrator.

Launch the Console application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Console in the icon grid.

Make sure the title of the Console window is All Messages. If it isn't, select All Messages from the SYSTEM LOG QUERIES menu on the left.

Scroll back in the log to the time you noted above. Select any messages timestamped from then until the end of the episode. Copy them (command-C) to the Clipboard. Paste (command-V) into a reply to this message.

When posting a log extract, be selective. In most cases, a few dozen lines are more than enough.

Please do not indiscriminately dump thousands of lines from the log into this discussion.

Important: Some private information, such as your name, may appear in the log. Anonymize before posting.

You have a hardware fault. Make a "Genius" appointment at an Apple Store to have the machine tested.

Back up all data on the internal drive(s) before you hand over your computer to anyone. If privacy is a concern, erase the data partition(s) with the option to write zeros* (do this only if you have at least two complete, independent backups, and you know how to restore to an empty drive from any of them.) Don’t erase the recovery partition, if present.

Keeping your confidential data secure during hardware repair

*An SSD doesn't need to be zeroed.

That's a site for people who waste their time trying to run pirated, hacked copies of OS X on PC's. It's irrelevant to your problem.

dawko wrote:

Thanks for your reply. I have found this thread

http://www.insanelymac.com/forum/topic/282859-nvidia-1082-opengl-channel-excepti ons-freezes-9600gt285gtx/

It seems that I'm not alone with this problem.

This issue has cropped up for others in the past (see here: https://discussions.apple.com/thread/1065674?start=0&tstart=0), and while some have seen it fixed with a hardware replacement related to GPU problems with MacBook systems, others have managed to fix it with an OS reinstall. The problem in the past was related to an OS update that seemed to pull it out of the woodwork for many systems.

The watchdog timer component of the Nvidia drivers is primarily for detecting when it is being used for driving a display, so the problem may be spurred by specific uses of the driver.

Does your system have dual GPUs? If so, then try going to the Energy Saver system preferences and try toggling the system's automatic graphics switching to see if that helps prevent the issue. Optionally you can try using the tool gfxCardStatus to force the system to only use one GPU (either the internal or discrete one), and thereby avoid any bugs that could be happening when the processors switch.

In addition you might try resetting the system's PRAM and SMC to see if those procedures help the situation at all:

Reset PRAM: http://support.apple.com/kb/HT1379

Reset SMC: http://support.apple.com/kb/HT3964

If not then the issue will likely require servicing. Apple did have a replacement program for some select MacBook systems, but this has likely expired by now.