Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!hplabs!hp-pcd!hpsgpa!plim
From: plim@hpsgpa.HP.COM (Peter Lim)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Perstor HD controllers
Message-ID: <340044@hpsgpa.HP.COM>
Date: 6 Dec 89 06:14:18 GMT
References: <6544@shlump.nac.dec.com>
Organization: HP Singapore IC Design Ctr
Lines: 49

> 
> Anyone out there used the HD controllers from PERSTOR ? I was wondering if
> they are worth the additional $125 or so over a WD1006 type controller.
> In particular, do they really work with MFM (non-RLL) drives reliably ?
> Is the disk capacity increased significantly ? Throughput ? Most important,
> how compatible are they ? Would OS/2 get confused by this type of controller ?
> I have a ST225 and a Quantum 530 that I'd like to use in an AT I'm putting
> together and thought their performance would be more reasonable with this
> controller.
> 
Here's my brief experience with PERSTOR controller. First let me mention
my setup.

One PERSTOR controller (probably an older model, but then I don't have
any reference).
25 MHz no cache '386 with AMI bios (which means can set bus speed to
either 12.5MHz, 8.33MHz or 8MHz), 8MB RAM.
One old Seagate ST225 harddisk (probably not very good one).

Okay, the bottom line is that I can't run the system at 12.5MHz bus speed;
so losing about 50% bus performance.
Second, I think I need to insert one wait state in the bus operation,
a further speed reduction. After getting everything working, I get about
250 KB/sec transfer rate by CORETEST which is about the same as normal
MFM controller.

The 40MB MFM drive was formatted to 78MB and I lost about 1.5MB to bad
sectors. After setting up, I ran Norton's Disktest every now and then
and had so far discovered another 4 to 5 clusters of bad sectors (no
big problem, right ?  :-)). Another annoying feature is that the damn
thing kept getting calibration error and have to rewind the harddisk
every 10 minutes or so.

Well, for me, I am not using the PERSTOR, no way ! Actually, I was
just borrowing it as a temporary stop gap till my ESDI harddisk arrive
(which is today).


Regards,
Peter Lim.
HP Singapore IC Design Center.

      E-mail address:              plim@hpsgwg.HP.COM
      Snail Mail address:          Peter Lim
                                   Hewlett Packard Singapore,
                                   (ICDS, ICS)
                                   1150, Depot Road,
                                   Singapore   0410.
      Telephone:                   (065)-279-2289