Just got my Aluminum Macbook with the Hitachi 5400 rpm drive 250gb. I have bought a Hitachi 7200 8mb cache laptop drive about a month ago. Should I put the 7200 rpm in my Macbook and the Macbooks drive in an external exclosure for timemachine. And what is the cache in the Hitachi 5400 found in the Macbook?
. You'll have to figure out how you want to transfer your data though. You can either do a clean install of OS X and backup your files manually or just use something like Super Duper to clone your current 5400RPM drive to the 7200RPM drive (there's a nice step-by-step guide you can google). With the 7200RPM drive your PC may seem "snappier" when opening programs/files and booting up/shutdown. Depending on the model it may be "noisier" though in the form of vibrations. And battery life may suffer a tiny bit if that matters to you.