Hi everyone Im a nube! Ok been around Macs for only 2 years and I love them. Im have a problem with a white Macbook 13' 160G HD 4 G of RAM . I had a heating issue where my fan broke took it in and the repair place replaced it but warned me the HD was making an odd rhythmic clicking sound. The odd problem is that every minute or it will prompt me "Are you sure you would like to shut down your computer now? " Everything seems to be working fine. other than that annoying prompt. Is my HD going? Everything was backed up. I wiped the HD and started over to no avail. Am I screwed or is there something I can do to stop the prompt?