My Inspiron 530 with Vista operating system sometimes wakes itself from sleep mode and goes to a black screen with the message "Hard-disk drive failure.  Press F1 to continue, F2 to enter SETUP."  If I enter setup and click "save and exit" without changing anything it restarts windows successfully.  I don't know if this is just a software glitch or a warning that my hard drive might be headed for failure.  Any advice will be much appreciated!