A graphics related bug that affected MacBook Pro systems upgraded to OS X 10.7 Lion has resurfaced for a number of people who have upgraded and subsequently updated their systems to Mountain Lion.
When Apple released OS X 10.7 Lion in 2011, a number mid-2010 model MacBook Pro owners found their systems inundated with crashes and graphics-related errors in which the system would show a black screen and freeze, requiring a forced shutdown and restart of the system.
This issue affected a number of people, and because some users were able to overcome the issue with a logic board replacement in their systems, it was suspected of being a hardware-related issue.
Apple eventually issued a software fix for the problem, but this appeared to be more of a workaround than a true fix.
While the software fix has kept this issue relatively silent, it appears in the latest updates to OS X 10.8 may have undone it a bit, causing these systems to experience graphics-related problems again. This time, instead of displaying black screens, the systems are largely experiencing kernel panics where the system's screen fades to gray with a message stating the system will need to be restarted.
The panic reports from these systems show the familiar model identifier "MacBookPro6,2" (the 15-inch mid-2010 MacBook Pro), and show the last kernel extensions being accessed before the crash as the graphics drivers for the Nvidia GPU. This model information can be looked up by choosing "About this Mac" from the Apple menu and then clicking the More Info button. In the window that pops up you will see the model name, such as "MacBook Pro 15-inch, Mid 2010." Additionally, you can click System Report and see the model identifier in the Hardware section of the report window. The model for affected systems is primarily MacBookPro6,2.
If you are experiencing these crashes on your system after updating OS X to the latest version, the workarounds that helped prevent this issue in the past may still apply now.
- Install gfxCardStatus
This issue has been identified as being triggered by the automatic switch between graphics processors when the system uses programs that demand more capability. By default the system will perform an automatic switch, but you can force it to use only one of the graphics processors and thereby avoid this behavior. To do this, one option is to uncheck "Automatic Graphics Switching" in the Energy Saver system preferences, but this will force the use of the higher-performance processor and lower battery life for some systems that require it.
The second approach is to install the graphics card manager tool gfxCardStatus, which adds a small menu extra to your toolbar that can be used to force the use of either the low-power or high-power graphics card.
- Get the system serviced
The next option is to get the system serviced, which will likely require a logic board replacement. Unfortunately this can be an expensive repair and is not guaranteed to be a fix, since the problem may be hardware based. However, some people have had success with this option.
- Wait for an update from Apple
The final option is to wait for Apple to update OS X to manage this problem again. In the meantime, you can use gfxCardStatus or even revert to a backup of your prior OS X installation to help avoid this problem.
Regardless of what you choose to do, one way to help the situation is to report the issue to Apple using its feedback page, and also be sure to submit any crash reports your system generates to Apple. These will help outline the issue so Apple's engineers can address the problem.