> I have heard that some disks have more sectors on the outside cylinders
> that on the inner ones. The geometry on the disk, i.e. the ratio of the

That's essentially what I heard, though I decided not to repeat what was,
for me, a vague memory.  Thanks for clarifying.  (^&

I'm also still not sure how many ``some'' amounts to.  Is it commonplace,
or rare?  Something that only expensive drives do?  (Most drives still
have RPM numbers associated with them; if they achieve the differing
densities by rotating at different speeds, then a single RPM is at best
misleading.)

I remember that older Mac floppies did this, but I think that they
eventually caved in to fixed-speed floppies.  (It was a bit of a sticking
point for emulating Macs, since most non-Macs did not have the
variable-speed drives.  One piece of software skirted the issue by only
reading a subset of the tracks---a set that had essentially standard
densities and could be accessed without a Mac drive.)


  "I probably don't know what I'm talking about." --rauch@eecs.ukans.edu