I've just purchased a 12 in. Powerbook and can't wait to get it!!! I've noticed on several posts that adding Ram through Apple is a rip-off, so I only got the 256 mb built-in. I went to Crucial.com from advice seen here and purchased a 512 mb chip to add. My question is...How hard is this to add and should I add it 1st thing before I start my computer up? Will adding this chip also void my warranty? Thanks for the help.