RAM and motherboards are the least likely suspect in kernel panics, but if you just have a new system, and or just installed new memory and you get a kernel panic, that's the most likely place to start looking. ... use the Hardware Test CD ...
Source: Mac OS X Kernel Panic FAQ
In my current job as jack-of-all-trades tech guy, I have to deal with everything. Lately, it’s been a 15” PowerBook that’s been having random crashes and happily corrupting its hard drive. Being a software guy, I run every program I can think of: Disk First Aid, DiskWarrior, fsck. Reinstalled Photoshop. Then, tried wiping the machine and installing OS X, which was fine until the installer itself crashed. Kernel panic after kernel panic. At one point, I considered consulting Eliza.
<p>Turns out it was the memory. We found this out by finally running the one bit of software that, as a software focused guy, I hadn’t even conceived of: The Hardware Diagnostics CD.</p>
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