[comp.sys.mac] Mac II internal HD's: 2 possible?

glen@cory.Berkeley.EDU (Glen Rosendale) (02/17/89)

I have a general question that I'm sure *somebody* can answer.  Is it possible
to install 2 internal hard disks in a Mac II? Easily? I can't think of a reason
why not, except that I've never heard anybody advertise the process or product.
Specifically, how about a 1/2 height 5-1/4" drive in the "normal" spot (where my
CMS 60 MB drive sits) and a 1/2 height 3-1/2" drive (possibly the Quantum 80 MB;
any comments about it?) in the spot *not* occupied by a second floppy drive.
There's only one SCSI connector on the motherboard, and my CMS has no piggyback
connector, but maybe somebody's drive does?

Thanks in advance for any replies (e-mail or post;  I do read this group
regularly & others might be interested).
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| Glen Rosendale	|    UC Berkeley	|  glen@cory.berkeley.edu     |
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steveg@tove.umd.edu (Steve Green) (02/17/89)

Two drive in a MacII is very possible.  All you have to do is make a new
internal scsi cable with 3 connecters on it.  The same goes for the power
cable.  Some companies supply a power cable with the option of another drive.
Also, I believe that some or all CMS drives have a wire cut on their cable.
Be sure to cut the same wire if you deciede to make a new cable.  Termination
MAY be a problem.  I dont remember if CMS drives are terminated but if you
put too many things on the scsi bus, you may have to pull off the terminating
resisters or experiment with different configurations.  Good Luck!

root@radar.UUCP (Donn S. Fishbein) (02/18/89)

In article <10011@pasteur.Berkeley.EDU> glen@cory.Berkeley.EDU (Glen Rosendale) writes:
>
>I have a general question that I'm sure *somebody* can answer.  Is it possible
>to install 2 internal hard disks in a Mac II? Easily? I can't think of a reason
>why not, except that I've never heard anybody advertise the process or product.
>Specifically, how about a 1/2 height 5-1/4" drive in the "normal" spot (where my
>CMS 60 MB drive sits) and a 1/2 height 3-1/2" drive (possibly the Quantum 80 MB;
>any comments about it?) in the spot *not* occupied by a second floppy drive.
>There's only one SCSI connector on the motherboard, and my CMS has no piggyback
>connector, but maybe somebody's drive does?

  This is possible and has been done. There's plenty of room and power inside a
Mac II. Basically, there's at least room for 3 3.5" hard drives, or a HH 5.25"
and a 3.5" hard drive. With the addition of a special bracket, available from
UniMac and probably others, you can substitute a full-height 5.25" hard drive
or two HH 5.25" hard drives into the previous sentence. Note that the use of this
bracket may impede airflow, and might not work if you've used high profile SIMMs for
memory expansion. You're responsible for any combination to add up the power
requirements and compare it to the Mac II specs.
  As for cabling, you need to consider power and SCSI. 4 conductor Y-cables for
power and commonly available for a couple of dollars (they're the same ones used
in IBM PCs). For SCSI, you're correct that few if any drives have two 50-pin
connectors. What you need is simply a SCSI daisy chain cable, a 50-pin ribbon cable
with 50-pin connectors spaced along it at appropriate distances. You may be able
to buy these prefab from mail-order dealers like Digi-Key, or you can easily
fabricate them yourself using bulk 50-conductor ribbon cable and ribbon-cable
connectors, which require no soldering.
  If this isn't enough detail, e-mail and I'll answer any specific question.

gshapiro@wpi.wpi.edu (Gregory N. Shapiro) (02/19/89)

Relax Technologies has a product which allows two internal Hard Drives
in a Mac II.  They include a special mount which replaces the one in
the Mac II.  The two drives are both 3.5".  Also, if I am not
mistaken, you can also daisy chain them in a way that the Mac thinks
it is just one big Hard Drive if you prefer.

						Greg

_____________________________________________________________________________

Gregory Shapiro                                               Gregory Shapiro
Worcester Polytechnic Institute               Worcester Polytechnic Institute
GSHAPIRO@WPI.BITNET                                                  Box 1397
GSHAPIRO@WPI.WPI.EDU (130.215.24.1)                        100 Institute Road
GEnie: THE.CYCLOPS                             Worcester, Massachusetts 01609
MacNet: GShapiro                                                United States
_____________________________________________________________________________

jth90342@uxa.cso.uiuc.edu (02/19/89)

>/* ---------- "Mac II internal HD's: 2 possible?" ---------- */
>
>I have a general question that I'm sure *somebody* can answer.  Is it possible
>to install 2 internal hard disks in a Mac II? Easily? I can't think of a reason
>why not, except that I've never heard anybody advertise the process or product.
>Specifically, how about a 1/2 height 5-1/4 drive in the "normal" spot (where my
>CMS 60 MB drive sits) and a 1/2 height 3-1/2 drive (possibly the Quantum 80 MB;
>any comments about it?) in the spot *not* occupied by a second floppy drive.
>There's only one SCSI connector on the motherboard, and my CMS has no piggyback
>connector, but maybe somebody's drive does?
>-------------------------------------------------------------------------------
>| Glen Rosendale	|    UC Berkeley	|  glen@cory.berkeley.edu     |
>| ++++++++++++++	|    ===========    	|  ----------------------     |
>-------------------------------------------------------------------------------


I needed to setup this kind of configuration a few days ago. I have an 80Meg
internal hard drive (the 3 1/2" Quantum), which through entirely my own 
fault crashed.  I was able to recover all 78Meg I had on it using the
Symantec Utilities.  However, my only options for doing the backup was to
archive onto approxiamtely 140 floppies or on a single volume that could
hold the entire contents. The only large hard drive I had access to was an
80Meg 5 1/4" Apple internal.  All that needs to be done to accomplish the
hookup is an IDC daisy chain cable and a Y power cable.  The IDC daisy chain 
cable is simply like the ribbon cable that currently connect the drive to the
motherboard, with the addition of another connector in the middle. The cable 
can easily be made with parts from any electronics store, with the most 
complicated thing being making sure that all the pin 1s match up (ie not very
tough...).  The Y power cable can be purchased from nearly any computer store
as it is the same cable needed to hookup 2 internal floppies in IBM PCs and 
ATs.  The SCSI protocol and hard disk drivers support the configuration without
any problem or modification.

The 3 1/2" Quantum 80Meg is an amazing drive.  It is blazingly fast and very
quiet.  I have never had any problems with it in extensive and abusive use.
The drive has an on board 64K RAM cache that speeds its already quick 19ms
access time to roughly 12-13ms.  I cannot recommend it highly enough.  If 
you are interested in purchasing one, I have a source that sells them for
$1075.  If you have any questions, call me or e-mail to:


                                              3 1/2" Quantum 80M source: 
       Jeff Huber - U of Illinois             Venture Computing
       ph. (217)356-6982                      701 Devonshire Dr., C-12
       email:  jth90342@uxa.cso.uiuc.edu      Champaign, IL  61820
                                              ph. (217)351-7084

mithomas@bsu-cs.UUCP (Michael Thomas Niehaus) (02/20/89)

In article <16003@mimsy.UUCP>, steveg@tove.umd.edu (Steve Green) writes:
> Two drive in a MacII is very possible.  All you have to do is make a new
> internal scsi cable with 3 connecters on it.  The same goes for the power
> cable.  Some companies supply a power cable with the option of another drive.
> Also, I believe that some or all CMS drives have a wire cut on their cable.
> Be sure to cut the same wire if you deciede to make a new cable.  Termination
> MAY be a problem.  I dont remember if CMS drives are terminated but if you
> put too many things on the scsi bus, you may have to pull off the terminating
> resisters or experiment with different configurations.  Good Luck!

Also you must remember that any internal drives that you buy must have the
built-in capability of using an SCSI address other than the normal value
reserved for internal devices.  If this cannot be changed, the two drives will
"attack" each other if both connected at the same time...


Michael Niehaus
Apple Student Rep
Ball State University
UUCP: ..!{pur-ee,iuvax}!bsu-cs!mithomas
AppleLink: ST0374

pfile@cory.Berkeley.EDU (Rob Pfile) (02/21/89)

In article <111900035@uxa.cso.uiuc.edu> jth90342@uxa.cso.uiuc.edu writes:
>
>The 3 1/2" Quantum 80Meg is an amazing drive.  It is blazingly fast and very
>quiet.  I have never had any problems with it in extensive and abusive use.
>The drive has an on board 64K RAM cache that speeds its already quick 19ms
>access time to roughly 12-13ms.  I cannot recommend it highly enough.  If 

	I can not recommend it highly enough, either. It is quite an 
improvement over the Q250 disk I had before.

>you are interested in purchasing one, I have a source that sells them for
>$1075.  If you have any questions, call me or e-mail to:

	This is a good price, but I just bought one from Hard Disks Int'l.
for $795, and much to my surprise this included a very nice anodized mounting
bracket and formatting software.

You can call them at (800) 234-DISK.

I have no affiliation with HDI, I am just a very satisfied customer.

Rob Pfile
pfile@cory.berkeley.edu
...!ucbvax!cory!pfile

glen@cory.Berkeley.EDU (Glen Rosendale) (02/21/89)

Thanks to all those who responded to my request.  Emboldened by knowledgeable
netters, I went ahead and installed the Quantum 80.  Here's a summary of the
process for those interested:

The physical mounting required a little modification of the bracket that came
with the Quantum.  It was designed to fit in the spot for the stock internal
hard disk, but only required a little cutting to fit in the second floppy's
place (the two tabs that anchor it are the same size for both brackets).
I did have to remove the internal floppy to mount the Quantum, and then put
the floppy back due to clearance problems getting at the screws on the
Quantum's bracket.

Power was no problem at all; a standard 4-conductor cable fit the motherboard
and drive connectors with no modification.  The SCSI bus wasn't too difficult
either, needing only about 2' of 50-conductor ribbon and 3 connectors.

I found the terminating resistors on both drives and removed the CMS's
because it was in the middle of the cable, and I set the Quantum SCSI ID to
0.  I'm beginning to wonder if I should have done that, because now the
machine doesn't always mount both drives on a reboot--I suspect the Quantum
comes up to speed much faster than the CMS and the CMS gets ignored.

In all, I'm very pleased with my current setup--I have Virtual installed,
and the difference in paging with the new drive is appreciable.  Not to
mention how *quiet* the Quantum is.

Thanks again to all those who responded.

( :^) isn't it nice when something works out right for a change? (^:  )
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| Glen Rosendale	|    UC Berkeley	|  glen@cory.berkeley.edu     |
| ++++++++++++++	|    ===========    	|  ----------------------     |
-------------------------------------------------------------------------------

ts@cup.portal.com (Tim W Smith) (02/24/89)

If you are willing to risk airflow, it looks to me like there is
room in there for at least 6 3.5" drives.  7 if you only need
one floppy.

Three go on top of the deck.  Four go *beneath* the deck.  There
appears to be plenty of room above the CPU/SIMMS/etc for disks.

					Tim Smith