We’ve heard many times that Apple Powerbooks are finicky about RAM (and that may be true), but it would appear that for owners of 15-inch Powerbooks, it might not be the memory that has the problem after all. A law firm is investigating claims that a fairly recent version of Mac OS X corrupted the firmware in the memory controller inside Apple Powerbooks, rendering the lower of two memory slots unusable.

If you’ve had a problem with your 15-inch Powerbook, you’ll probably want to fill out their form to get a potential piece of the class action. Judging from the Engadget, Powerbooks under warranty can have the problem fixed by replacing the logic board.

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