I have a 2GHz unibody macbook which I got about 3 weeks ago. I installed 4gigs of ram myself and a WD Scorpio 320gig 7200rpm harddrive. I notice things like typing and animations within OSX seem to be a bit laggy. Whenever I pull down with all four fingers on the trackpad and show all the programs, the animation isn't smooth, but "jagged", like moving at a slow frame rate. Same thing when I minimize/maximize windows, and switching between tabs in Safari also sometimes takes a while (sometimes bringing up the spinning beach ball). Same thing with typing in web addresses, sometimes taking a second before registering any of the key presses. The 2 year-old plastic iMac's at school seem to run better than my brand new Macbook. Does anyone know if there might be a problem? Am I overreacting? Would reformatting fix the problem? Any help would be appreciated. Thanks.