For anyone that follows my blog/Twitter/Facebook griping, you will know that my mid-2009 13″ MacBook Pro could not be upgraded to anything beyond Mac OS X 10.7.3 because it would kernel panic constantly.
For some reason, the MBP would be completely stable in 10.7.3, but anything beyond including 10.7.4, 10.7.5, or 10.8+ was completely unusable; random kernel panics anywhere between a few minutes to a few hours after a cold start.
Initially I did some memory tests and they all passed so I assumed the RAM was good and ended up restoring all the factory hardware (I have aftermarket SSD and SATA drives) and it still had issues.
See my original post from August 2012 to read about my troubleshooting: https://www.ocabj.net/kernel-panics-in-mac-os-x-10-7-4-and-10-8-solved/
A couple days ago I came across a response/post in the Apple Discussion boards where someone had kernel panic issues and stated that he replaced the RAM because his aftermarket RAM upgrade is not compatible with 10.7.5. I thought that was odd. How can RAM be incompatible with a later revision of the same OS on the same computer?
But I thought about it for a while because I had actually purchased ‘general’ all-purpose Crucial RAM from Newegg which technically was the correct specification for my MBP (DDR3 PC3-8500, CL=7, 1066MHz, etc), rather than buying RAM that was specifically “Mac approved” / “Mac Compatible”.
I went to the Crucial website and used their memory selection tool for my respective laptop and decided to shell out $60 for new RAM. When I received it, the labels indicated the SODIMMs are “Mac Compatible” memory.
I swapped the RAM out, updated from 10.7.3 to 10.7.5 and ran for 24 hours without any issues, and decided to bite the bullet and reformat and install 10.8.x. I have been running Mountain Lion for 48 hours without a single Kernel Panic and it appears that the RAM indeed was the culprit.
But the mystery is whether or not the old 2x4GB Crucial SODIMMs are actually bad or if the RAM simply is not running within Apple specifications.
The computer is completely stable in 10.7.3, but then unstable in 10.7.4 (or later). It’s just odd that bad RAM would be fine in one revision of an OS and not another, so my assumption is that my initial Crucial RAM upgrade wasn’t truly within Apple specifications.
Anyway, I think I finally resolved my Kernel Panic issues on my mid-2009 13″ MacBook Pro.