yesterday i booted up my dual 2.0 g5, reinstalled leopard on it and set it up to be a secondary pc for my parents/other family members/visitors if they quickly needed to look at the weather forecast, watch a youtube video etc. i used youview to watch youtube video's when i still used the machine as my daily driver (half a year ago), and that worked fine with 720p video. but now it stutters like hell and only plays back 480p video soothly. what could be wrong with my machine that it doesn't play 720p anymore?