Hey, thanks for the quick help. I forgot to mention that I set already the screen saver to “never” for monitor & HDD and still does not really care. I understand the idle mode of LW, but it goes to sleep when I am having full activity like surfing, writing an email in entourage or changing the info of a song in itunes, no matter if LW is open or not. I associate it with LW because when I uninstalled it the computer became more stable. I have an imac5 with all updates installed. Any suggestion?