I used to remember an old Linux magazine article (which I no longer have) that discussed some commands you could type to see how healthy your disk drive was. Evidently there was a very special command you could run that would tell you a calculation on how many more years your disk was good for, or something like that. Somehow it interfaced with the BIOS of the disk drive. It was different than fsck. Do you know what command or commands I'm talking about?