[Info-vax] Alpha Personal Workstation question

[John Wallace]

On Aug 9, 10:12 pm, Steven Schweda <sms.antin... at gmail.com> wrote:
> > Thanks. Do you by chance remember if you tried double sided modules or
> > single sided ?
>
>    I'm not absolutely sure which of the junk in my "Useless
> Memory" pile was the stuff I tried, but my best guess is the
> modules with the labels:
>       512MB Sync 100MHz, CL2 ECC
> and:
>        Compaq
>       110959-042
>
>    These very closely resemble the modules in my "Good Memory
> for XP1000" pile, with the labels:
>       256MB, Sync, 100MHz, CL2, ECC
> and:
>        Compaq
>       110958-032
>
>    The boards themselves look equivalent (apparently made by
> a different board maker, but with the same etched-in-copper
> number on the front:
>       PS512166NESS6GCX
>       REV. C
> and the same "SMART (C) 2000" on the back.
>
> The (Samsung) memory chips (nine on each side) are different:
>       256MB: K4S2804328-TC1H
>       512MB: K4S560432A-TC1H
>
>    All the boards are silk-screened "ASSEMBLED IN USA", so
> you know they're old.  (These are the modules I have loose.
> The ones I have installed in my XP1000 systems at the moment
> may be different, but I have tested these (256MB) modules in
> XP1000 systems.)
>
>    I mostly stopped caring about my PWS when I got an XP1000,
> but, as I recall, I had trouble if I filled the thing with
> these (256MB) modules.  If I installed one pair of the
> official (more-expensive, taller, more-chips?) DEC modules,
> then I could use these for the remainder.  (I've had no
> trouble with them in an XP1000.)  A search through old
> comp.os.vms postings may find more details.  I never tried
> the 512MB modules in the PWS, but, seeing the failure in an
> XP1000, I would not expect success in a PWS.
>
>    At the rate "Secure Web Browser V1.1-12" ("based on
> Seamonkey 1.1.12") eats memory, I wish that I could get more
> than 2GB in an XP1000, but I've given up hope.

The "SMART" reference is probably SMART Modular Technology, who did
contract manufacturing for a lot of more well known names. They also
ended up being temporary owners of much of DEC's Embedded+Realtime
sector at one point.

There was/is a selection of DTJ (Digital Technical Journal) articles
on the PWS design, findable at e.g.
http://www.hpl.hp.com/hpjournal/dtj/vol9num2/vol9num2art4.pdf for the
first one (article 5 is about the memory subsystem design). Nothing
obvious I could see about maximum memory capability, but an
interesting read (if that's your kind of thing), and someone who
understands more about memory system opertation than I do *might* be
able to read between the lines and work out whether bigger memory
stands a chance.