All the DECstation 3100's I remember seeing had a standard narrow 
"SCSI-2" mini connector on the back.

----------
From: 	Simon Burge[SMTP:simonb@telstra.com.au]
Sent: 	Tuesday, September 17, 1996 8:59 PM
To: 	Jason Thorpe
Cc: 	John C. Hayward; port-alpha@netbsd.org
Subject: 	Re: What kind of SCSI interface on the UDB=20

On Tue, 17 Sep 1996 19:59:40 -0700  Jason Thorpe wrote:

> On Tue, 17 Sep 1996 21:40:52 -0500 (CDT)=20
>  "John C. Hayward" <John.C.Hayward@wheaton.wheaton.edu> wrote:
>=20
>  > with another system and then boot off of the "borrowed" drive.  I 
have
>  > a drive which plugs into a DecStation - 3100.  Is this the same 
SCSI=20
>  > connector on the UDB? =20
>=20
> The connector on the UDB (Multia) is a 50-pin mini connector (a'la=20
> SPARCstations).  The connector on the DECstation is the 
Centronics-style,=20
> I think...

It's worse than that, the MIPS DECstation 3100 has a funny "wide"
honda-style connector that doesn't seem to be compatible with anything
else I know off.  You may have to resort to putting your disk _in_ the
3100 for now...