I have a Core Duo Macbook and I upgraded the stock 512MB RAM (2x256MB) to 2 GB. My girlfriend has a Core Duo iMac with the stock 512MB RAM also. Would it be possible to put one of my old ram sticks into the iMac? Or does the iMac have 2x256MB sticks like the Macbook did? I think they use the same kind of RAM, but I wasn't positive. Thanks for any insight.