Lacero said:Is there an empty RAM slot available or did apple fill 512MB of RAM by giving us 2x256MB sticks?
Think about how you could answer this question yourself.... why dont you go to the apple store online and look at the maximum ammount of memory you can put in the ibook if it says 1.256 than that means they use two 256 sticks if it says it's upgradeable to 1.512 that means they use a single 512 stick...