i'm experiencing glitching when playing video. mostly .avi on vlc - the video will stop for a second, pixelate for a few seconds then go back to normal. i was experiencing some glitching in safari as well (shortperiods of beachballs) so i upgraded to a momentus xl hard drive (500gb 7200rpm hybrid) and now i have no issues remaining except the video. i'm on a c2d white macbook, 2.4 ghz and have just done a clean install of snow leopard. machine is running great with the new drive but if anyone knows what the hitch with videos might be i'd appreciate the insight - thanks.