[comp.sys.ibm.ps2.hardware] PS/2 Hard Disk Upgrades

CES8@psuvm.psu.edu (03/06/91)

                      IBM PS/2 30-286 Hard Disk Upgrade
                      ---------------------------------


     I have upgraded my PS/2 30-286 with a Seagate ST1096N SCSI hard disk
(85 MB, 24 msec average access time). To keep the costs down I used an ST-01
SCSI controller (I spent under $400). A better controller such as the Future
Domain, Adaptec or Western Digital would yield better performance (16 bit
controllers).

     The procedure is very simple, the ST1096N is a 3 1/2" drive and it fits
in the hard disk bay of the PS/2 line. A skid plate is necessary to mount the
drive. I used the skid plate from my old 20MB drive, but they are also
available from J&L Marketing and PS Solutions (they are cheap).

     The catch in the internal installation is that the PS/2's do not have a
standard power connector for the drive (this is a 4 pin connector). A simple
way to bypass this limitation is to use a controller that has a power connector.
The Seagate ST-01 and some Future Domain controllers have such connector. I have
not checked the Adaptec or Western Digital controllers. I made my own power
cable to connect the power from the controller to the drive. The SCSI cable
came with the drive.

     I configured the system without the controller installed (no hard disk)
after removing the original hard disk. Then I installed the SCSI controller,
drive and cables. This procedure is also suggested by Seagate's Tech Support.

     The next step is to power up the system with a DOS floppy (I am using
version 4.01). I performed the low-level format by invoking the procedure from
the controller's BIOS (using DEBUG). With the ST-01 controller the best
interleave factor is 2:1. I chose not to use Disk Manager, so I used FDISK to
create one 85 MB partition and then formatted the drive. I installed DOS using
SHARE to support the large partition.

     The entire installation took about 30-40 minutes and I didn't run into any
problems. The drive performs much better than the original IBM drive, the access
time is improved by about 60%.

     As for compatibility, I haven't found a single glitch. I have Windows 3.0,
Word for Windows, Norton Utilities (but I wouldn't try calibrate), MS Fortran
and a many other packages running without any problems.

     Some interesting notes: You can keep your old drive and install the new
drive as D by using a drive-on-a-card frame since the ST-01 is a short
controller (J&L Marketing has these frames). You can also install the new drive
in an external enclosure (this way you can use a 5 1/4" drive), but hard disk
cases with power supply are not cheap.


                     IBM PS/2 Model 50 Hard Disk Upgrade
                     -----------------------------------


     I have also helped with 2 PS/2 50 hard disk upgrades. The only difference
is the use of a microchannel SCSI controller (Future Domain, Adapetc and
Western Digital have MCA controllers). The procedure is essentially the same,
including the need for a power connector (internal installation).

     If the new drive is installed in the B drive bay, it is necessary to
realign the drive on the skid plate because of the floppy connector on the back
of the drive bay. New holes have to be drilled for mounting the drive on the
skid plate, but that is a minor problem.

     I hope this information helps the people considering upgrades. Also
consider that there are other options such as an external drive installation
or other interfaces other than SCSI.


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*      C.E. Soares          CES8@psuvm.psu.edu                                 *
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*      Standard Disclaimer Applies                                             *
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