It seems sometimes, at random really, if i leave my computer for a while and come back (say over night or several hours when at school) it will just be a black screen and nothing loads on the screen. I hear the hdds spin back up, i wait and still nothing comes out. At this point i always hit the power button which instantly turns it off and i have to turn it back on. Any reason why it would be doing this? I have it set to turn off monitor after 3 hours, don't tell it to sleep and have no screen saver.