[comp.sys.ibm.pc.rt] details wanted for EESDI controller and disks

dyer@arktouros.mit.edu (Steve Dyer) (04/03/89)

Well, in preparation for eventually receiving my APC upgrade[*], I'm
looking into cheaper alternatives to the stock IBM ESDI disks.  I
have one 114mb IBM ESDI disk which I will use, but I want more fast (and
more affordable) disk space than that alone.  I don't have the money
for another IBM disk with the capacity I need.

I'm presently using 3 ST-506 drives of mongrel geometries and
manufacturer (2 Miniscribe 70mb and 1 Maxtor 120mb) with great success,
requiring only the simplest of driver tweaking for different partition
tables.  Ordinarily, I'd just assume the same could be done for ESDI
disks, except that I have heard that there are both "hard sectored" and
"soft sectored" ESDI disk drives, and a particular controller may
support only one of these types.  I've had friends who got burned
buying the wrong ESDI drive for their controllers in the PC/AT market,
and I don't want to make the same mistake.

Does anyone know which kind ESDI disk (hard/soft sectored) the
RT EESDI controller expects to find?

Also, I have been told that the IBM H310 310mb ESDI drive is actually
manufactured by Maxtor.  Does anyone know the Maxtor model number for
this drive?

Thanks, as always.

Steve Dyer

[*] I was finally assigned an IBM salesperson in mid-January.  I have
    not actually received a written confirmation in response to my
    order letter of 1/19/89 that an order for the APC upgrade has been
    placed.  That is, I have no paperwork in hand showing me that an an
    order has been placed in my name.  When my salesperson received my order
    letter, I was verbally quoted "4th quarter 89" delivery (!!!),
    although my casual non-sales IBM contacts lead me to believe that
    this is probably excessively pessimistic.  However, subsequent
    phone messages to my salesperson requesting an update on the status
    of the order go unanswered.  I'd be happy with a response of "no
    news yet".  But I don't hear much of anything.  This is a small
    improvement over not being able to order an APC upgrade at all,
    but only a small one.

---
Steve Dyer
dyer@arktouros.mit.edu
dyer@spdcc.com aka ...!{harvard,linus,ima,m2c,rayssd}!spdcc!dyer

edler@cmcl2.NYU.EDU (Jan Edler) (04/05/89)

We've happily used two Micropolis drives.  We run AOS, if it matters.
The drives we've used are

	model 1355	(8 heads, 170.6MB unformatted)
	model 1558-15	(15 heads, 382.3MB unformatted)

They seem to support both hard and soft sectoring; I don't have the jumper
info at hand but I think what you need is soft sectoring, with 36 sectors
per track.  Anyway, we've used those two drives with EESDI controllers.
I'm sure there are others that work too.

Jan Edler
NYU Ultracomputer Research Lab
edler@nyu.edu