Ethan Dicks ethan.dicks at
Mon Apr 29 21:55:36 CDT 2019

On Mon, Apr 29, 2019 at 12:44 PM allison via cctech
<cctech at> wrote:
> On 04/29/2019 11:37 AM, Jon Elson wrote:
> > On 04/29/2019 06:47 AM, allison via cctech wrote:
> >> On 04/28/2019 09:28 PM, Grant Taylor via cctech wrote:
> >>> On 4/28/19 6:27 PM, Ray Jewhurst wrote:
> >>>> I already have a Hobbyist License.  I am just interested in
> >>>> experimenting with different OSes and different versions of OSes.
> >>> ACK
> >>>
> >>> I don't know what VAX hardware VMS 1.5 supported, what VAX hardware
> >>> that Simh supports, or what the overlap is between the two.
> >>>
> >> You are limited to what the VAX-11/780 system had for peripherals and
> >> typically under 8MB ram (it maxed at 16mb).
> The typical environment during the DEC years '83-93 was a 780 with a
> 4-12mb and dozens of users or more.

We (by that I mean Software Results) had an 11/750 that started out
with 512K of RAM and quickly upgraded to 2MB.  I later bumped it up to
8MB (adding the backplane wire and replacing the memory controller)
and we ran 40+ users on it.

> In 83 that meant 3.2 or later and much of the time was V3.8 or 3.9 till
> maybe 86ish then V4 and soon after V5.

I first encountered VMS in late 1984.  I started off a just a user, so
I don't recall the version, but ISTR we upgraded to either V3.4 or
V3.6.  We stayed there for a while, but the MicroVAX I we got was
upgraded from, MicroVMS 1.0 to MicroVMS 4.0 as fast as that came out.
Eventually we did the upgrade path to 4.0 and beyond, pausing at 4.6
on that machine in part because we had a SI9900 controller (you had to
patch DRDRIVER.EXE to use all the cylinders of a Fuji Eagle) and in
part because we had customers who were still on V4.X.  I put
V5.something on an 11/730 and we used that box to link our product for
newer versions of VMS (after 1988).

When we shut everything down in 1993, we were still running VMS 4.6 on
that 11/750 and never needed to upgrade it past 8MB.  It did have
about 1GB on 4 spindles and 2 controllers.

> The years 83 and 84 I fondly remember V3.6 and later mostly V3.8...

I definitely remember V3.6 but I don't think we were on V3.8 for very
long before moving to V4.0.

> If memory serves V4 was the last that ran in 1meg, V5 pushed that higher
> as a 4 meg system was more common then.

I don't think I ever tried to run V4 in under 4MB (even our MicroVAX I
was maxxed out).  Or MicroVAX II had 9MB (and I think we had that one
on V5.4 for a while before moving to V5.5-1).  I think our VAX 8200
was on V5.4 for product development (COMBOARD for VAXBI) and it had no
less than 8MB (the total amount varied by how many slots we had to
free up by removing 2MB boards.

> However the Qbus uVAX has a RD54[system] and RD52[swap] on
> separate MSCP controllers
> for performance as thats where they bottlenecked when heavy swapping.

That sounds like fun - we never had enough hardware to pull that off.

> All my uVAXen have run from V4.4 [MicroVaxII/GPX] or later and my
> nominal version is 5.4.  Though I have a
> RZ56 with V7.2 on it.   All are physical hardware in the Qbus BA123
> realm and M3100 series.

Cool.  I've powered up the MicroVAX II in recent memory, and the VAX
8200 but I haven't fired up the 11/750 since the company folded.

> Running anything before V3 is painful as it was a build.  Also V1 was
> tied the 780 and that did PDP11 emulation
> mode for a lot of stuff.

Like I said, I started with V3.x so I missed out on the "joy".

> VMS changed a lot from 4.2 to 4.6, long file
> names are one that comes to mind as well as
> phase III and IV DECnet.

Yep.  Lots of changes, most of them improvements.

> That was a long time ago.

It sure was.


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