On 16 Oct 98 at 11:14, Mike Morgan wrote:

> The 40-pin ribbon cable has two connectors on it, and those are
> being used by my current hdd and the CD.  I'd like to ADD this
> second hdd to the mix (as opposed to simply replacing the current
> one).  Can I simply purchase a new ribbon cable with 3 connectors?

  No.

  [My first inclination would be to wish you luck finding one, but I
happen to know that our local superstore, Fry's, recently erroneously
stocked a bunch of 40-pin cables with 8 connectors....]

  The interface which your hard drive and CD-ROM are using is called
"IDE" -- there's also an "EIDE" (Extended IDE) which will work with
the same devices.
  Central to IDE is the idea of a "channel", consisting of a master
device and an optional slave device, connected to an "interface"
(which gets called a "controller", even though it doesn't do much of
what controllers have traditionally done for drives...).

  A standard IDE interface provides one channel, for up to two
drives.  This sounds like exactly what you have.
  An EIDE interface provides two channels; each is still limited to
two drives.

  There are three basic options:

1.  You could install a second IDE interface.  If you go this route,
you probably want to move your CD-ROM to this second interface and
put both hard drives on the primary.  Some sound cards include an IDE
interface for exactly this purpose.
  [Caveat:  There are at least three other CD-ROM dirve interfaces,
which use 40-pin connectors but are *not* compatible with IDE, which
may also be found on sound cards that are a year or two old!]
  [Particularly with older drives, a CD-ROM drive may slow down
throughput to any hard drive on the same channel.  Newer CD-ROM
drives, and UDMA-capable controllers, avoid that problem.]

2.  Replace your current IDE interface card with an EIDE interface
card (which will offer two channels).  In 486 days, my preference was
for the DTC 2278-E card (2-channel EIDE, floppy, parallel, 2 serial,
1 game port on a single card) for VL-bus machines, or the similar DTC
2280 for ISA.  You may still be able to find these, or cards like
them.  There was also a 2278-EB version with LBA BIOS extension --
more about *that* issue in a moment.

3.  You may already have EIDE, and just don't realize it.  I seem to
recall that IDE was limited to about 500 MB/drive, so (a) some CDs
may be only partially readable with IDE, and (b) drives larger than
500 MB probably aren't happy with it either.  If there is a second
40-pin connector next to the one that the current drives are plugged
into, you're in luck!

  Even with an EIDE interface, that other hard drive is going to be
limited to about 500 MB unless (a) your system BIOS can do LBA
(unlikely in the configuration you describe), (b) some device
provides a BIOS extension to add LBA (see the mention of the DTC
2278-EB above...), or (c) you install EZDisk or some other software
that deals with the problem (a poor third choice...).

David G

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