I bought a 27" iMac i7 with 8gb of ram... fully loaded and after partitioning my drive started getting pinwheel problems with the default 5400 rpm harddrive. I did a fresh install and didnt have the problems anymore. Again I put bootcamp on and there are still pinwheel issues. I went to apple and they replaced the harddrive a saying that partitions take a pie like slice out of your drive and it shouldnt effect speed. They replaced with with a 7200 rpm harddrive. All was well until I partitioned the drive again. The weirdest part is that windows runs at 10000 mph where 10.6 pinwheels no matter what I do... I am fairly tech savvy and feel like this is maybe a defragmenting issue... I believe osx defragments files under 20mb... could this be it? It is driving me bonkers... I use both windows and osx and need to boot completely into the OSs as I am using primarily post programs like after effects... any advice would be greatly appreciated.