iMac (Mid-2007): Repeated crashes after Software Update 1.1; graphics-related

A number of readers are reporting more frequent system freezes/crashes from their Mid-2007 (Aluminum) iMacs after applying the iMac Software Update 1.1. It's important to note that many users were having issues with random shutdowns and other problems before the update, which seem to have been exacerbated by the software update. For instance, some users are reporting that their iMacs are now crashing from something as simple as mousing over the Dock. The consensus among users appears to be that some iMacs' graphics cards are problematic, and the software update, which contains updated graphics drivers, makes the problem worse in some cases. This means that not all machines are affected by this issue -- only those that appear to harbor the flawed graphics cards.

This Apple Discussions thread has some typical reports, all pointing to some sort of graphics-related issue:

• "I've had a 24" iMac for about a month, and have never experienced the dreaded freezing issue. Now that I have Update 1.1 on my iMac however, I have a real hard time making it not freeze. What's interesting is that every time it freezes, only the mouse moves - so I think the system is seriously hosed. Not so! I can ssh into the machine still from another computer and run a variety of command line applications without issue."
• "I have experienced all the listed issues on my 24". The screen goes black, sometimes the environment freezes but the mouse is moveable, and once the screen froze and the sound started to jitter."
• "(My iMac) is crashing all the time. Mouse moves, volume goes up & down from keyboard, etc., but that's about all it will do. Sometimes I get the artifacts (screenshot works) but often it just gives up the ghost. I even get the startup issue that some are speaking of, with the pale blue screen. I'm searching all these posts for an answer, but not finding one. I hoped the update from Apple would help, it didn't."

Solution In some cases, this issue can be eliminated by downgrading to the previous edition of the iMac software update, which contains the older, perhaps less problematic graphics card-related files. This can be accomplished via the following process:

1. Download iMac software update 1.0.
2. Download Pacifist
3. Drag the iMac software update 1.0 package over the Pacifist icon to open it.
4. Select the package in pacifist (the top item in the list)
5. Click the "Install" button, and check the box next to "Use administrator privileges"
6. After installation is complete, restart your iMac

Feedback? Late-breakers@macfixit.com.

Resources

thread

Download iMac software upd...

Pacifist

Late-breakers@macfixit.com

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