hey, sometimes i run a lot of programs with only 512 mb of memory. my i stat tells me that i only have 5 free mbs and after that it slows down considerably. i close most of the programs but still it is running very slow. then i restart my computer and it does not seem to restart from the apple button. it just stays at my wallpaper image. i have to press and hold down the on and off button. i was wondering what my computer is doing. thanx.