In message <200203301019.g2UAJDs0078498@w3.bluegrass.net>, you write: 

-> 520 bytes per sector looks weird, I didn't know such a disk existed, 
-> would have thought sector size would be a power of 2.  Are you sure
-> you read the datasheet correctly?

I don't know about this particular instance, but I picked up a bunch of
Tandem-OEM'ed IBM drives that were all formatted to 520bytes/sec.  Dunno
what the advantage of that configuration was, but I merely re-set the 
config to something more resembling a workable config (512b/sec) and
everything worked OK.

I know that when I read the datasheets for those drives, IBM claimed
to support a range of sector sizes around 512b/sec (both smaller and
larger) IIRC.

--rafal

----
Rafal Boni                                                     rafal@attbi.com
  We are all worms.  But I do believe I am a glowworm.  -- Winston Churchill