NT can do RAID 5 through software, which is striping with parity (redundancy
and performance).  The suggestion to go with at least 3 SCSI drives is good,
since a minimum of 3 are required to obtain a RAID 5 configuration.  To do
this, you can go to Disk Administrator, select your 3 new drives and choose
Create Stripe Set With Parity from the Fault Tolerance menu.  Choose the
size (max) and click OK.  Check the event log frequently, because if one of
the drives in your stripe set fails, you won't know it otherwise.  If one of
your drives does quit, you can replace that drive, go back into Disk
Administrator, select the stripe set to be repaired as well as the new disk
and from the Fault Tolerance menu choose Regenerate.

If your drive configuration is found to be the culprit (and not the
processor; use performance monitor to find this out), I would get the
AHA-2940U2W Ultra2 Wide SCSI controller (80 MB/s) with 3 or 4 Cheetah 4.55
gig (ST34502LW) drives.  Your processor should still be fast enough to
outpace this setup.

This setup will cost you roughly $600 per drive and the controller about
$380.  If you can't afford this, then go with the setup outlined below (3
IBM DCAS34330 4.3GB drives and the AHA-2940UW) configured as RAID 5 in NT.
If you can afford it, get one more DCAS34330 4.3GB drive for a total of 4
drives and greater redundancy/performance in your RAID 5.

Dan Dexter
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-----Original Message-----
From:   PCBUILD - Personal Computer Hardware discussion List
[mailto:[log in to unmask]] On Behalf Of David Gillett
Sent:   Wednesday, June 03, 1998 2:25 PM
To:     [log in to unmask]
Subject:        Re: [PCBUILD] Ultra Wide SCSI Harddisk on NT4.0

You're likely to get better SCSI performance with multiple drives
rather than a single large drive.  If you can afford to put the swap
file on its own drive, that will help -- even more if it's on its own
controller.  For the rest of your files, you want to spread accesses
across several drives, and you can do that automatically with a RAID
array.
  NT can do RAID 0 and RAID 1 in software.  For performance, you want
RAID 1, but the disadvantage is that if any drive dies, *all* of your
files are lost.  To cover that, you need to go either to RAID 5 or
RAID 0+1, and I don't think NT will do either on its own.  RAID
hardware controllers typically run in the $1-2K range; if you're
interested in those, skip the 2940UW...

  My recommendation:

1.  Keep the 2.1GB drive as the boot drive.  You can't boot from a
RAID array if NT is doing it in software.  I'd try putting the swap
file on this drive, too.

2.  Add the AHA-2940UW.

3.  Instead of the ST39173-W (note corrected model #), about $650,
install 2 or 3 IBM DCAS34330 4.3GB drives, $280 each, and configure
them in NT as a RAID 1 array ("stripe set"), which means that they'll
look to applications and users like a single 8.6 GB or 12.9 GB drive,
with roughly 2 or 3 times the bandwidth to disk of a single drive
(subject to the UW-SCSI maximum of 40MB/s).