I need an answer as to why a drive fails to boot intermittently and what "MAXTOR DRACO100 DAC10SCZ" means when it fails as opposed to "MAXTOR 53073H6 DAC10SC0" when it does boot. It makes a squealing sound when it isn't going to boot. Sometimes it takes 2 or 3 tries to get started. Sometimes it will boot several times in a row with no problem. Very aggravating. Warped drive? Bios not good at picking up 7200rpm? Am hoping someone else has already solved the same problem. Thanks for any replies.