My 80GB Maxtor seemed to have started to error (including CRC errors on moving some files)_ so I bought a new Samsung 200GB to replace it.
With both on a Promise UDMA 100 controller I used MAXBLAST to copy the disk.
Then I found that there were a great many more errors on the copy than the original.
Comparing the files which were different showed the same pattern at each difference - where the original disk had 8 bytes, the copy has only 2 bytes and they are a duplicate of the preceding 2 bytes and not any of the 8 missing bytes.
I expected to see 512 byte zones of garbage... so I was a bit surprised by this result.
Does this pattern of differences give any clues as to the source of the problem? - is it possible the controller or motherboard rather than the disks which are causing problems?