[Info-vax] Out with Hurd, in with OpenVMS

[John Wallace]

On Aug 19, 1:38 am, Michael Kraemer <M.Krae... at gsi.de> wrote:
> DaveG schrieb:
>
> > From:  http://en.wikipedia.org/wiki/DEC_Alpha
>
> > "At the time of its announcement, Alpha was heralded as an
> > architecture for the next 25 years."
>
> > I recall this statement was made more than once at the DECUS symposia
> > back in 1992.  I think 1992.
>
> That's what DEC marketing claimed.
> Contrary to common belief, DEC *had* marketing back then.
>
> > Also recall some (the guys with the slower chips at the time) were
> > complaining the Alpha chip ran too hot.  So rather than take the heat,
> > DEC had an Alpha system they cut a hole in so one could touch the cool
> > future on the exhibit floor.  I touched - it wasn't hot.
>
> Which of the early Alpha systems had their CPU
> oriented towards the outside?
> Whatever you touched, most probably it wasn't the Alpha CPU.

[missed this earlier]

Which of the early Alpha systems had their CPU oriented towards the
outside? Well, here's a list using the definition of 'outside' that
seems reasonable to me. Readers will have to select from it based on
whatever "early" means, but the list includes every low end system
from the first EV4 systems up to EV5x workstations.

Start in 1992 with the DEC 3000 deskside and tabletop TURBOchannel
EV4/21064 machines (the "bird" machines, Flamingo, Sandpiper, Pelican
etc).

SLightly later than that, the Jensen/DECpcAXP150 EISA desktop box,
then the AlphaStations 200, 250, 400, 500, 600, PWS/Alpha workstation,
etc. And even some of the low-end servers eg AlphaServer 1000. And
also the XP900, the XP1000, and the DS10 (though that's not really
"early" any more).

All of these systems with the exception of the AlphaServer 400 (aka
Avanti) are basically built around a single main board which has the
(single) processor and the core logic on it, in an enclosure which
exposes the main board and thus the processor when you take the lid
off (or side off).

In the AlphaStation 400 the CPU is still easily accessible with the
side off, but it is on a daughterboard which came in variants for
Alpha or x86.

Some of the others use daughtercards for IO but they all basically
follow the same fundamental principle - one big active card containing
the majority of the electronics, including processor, memory, etc.
(Pedants may note that the PWS family follow the AlphaStation 400
principle of a core design shared between an x86 system and an Alpha
system, with processor-specific stuff on a daughtercard, which by this
time was in the industry-standard NLX form factor (which died off when
Dell decided to go for proprietary form factor desktop boards, which
is a reminder that even after DEC went away this "proprietary" stuff
lives on in some markets).

Many (most?) Alpha chips came with two substantial brass bolts baked
on to the ceramic chip enclosure, to ensure thermal conductivity
between silicon and heatsink was good enough to allow cooling without
a fansink, because industry opposition was initially claiming that the
heat dissipation would be an issue. It was so much of an issue that
the EV4's maximum dissipation would have been considered routine in
the Xeon market in recent years.

DEC3000 DTJ article with pictures: http://www.psych.usyd.edu.au/pdp-11/alpha_specs.html

Lots more pictures of Alpha chips and mainboards: http://ummr.altervista.org/DEC_Alpha.htm
(text mostly in Italian)