For the last month or so, when the powerbook should go into screensaver standby mode instead it began flashing and beeping away rapidly until i either move the mouse or press a key. I have extended the time when the computer goes into sleep or when it should go into screensaver but appears not to have made any changes. It still flashes on/off and beeps the alert sound approximately after 3 minutes from when the last key or mouse movement took place. Can someone with the knowledge please advise how to overcome this problem, I have installed and updated Norton Internet security/ anti virus which made no difference, but have been advised that it appears to be a hardware issue??? HELP!!!