The way I understand it, IDE drives should automatically map out bad blocks, (is this true for all IDE drives?) whereas MFM disks won't. Therefore I'd assume that once an IDE drive starts presenting bad blocks to the user its days are pretty numbered... I was once told that a small percentage of an IDE disk is unused, purely for the sake of providing a "reserve" area so that the disk could cope with some bad blocks whilst still giving the user the impression that full capacity was available - is this true, or just one of those stories that I happened to turn up over the years?? cheers J.