I think that
the 3/50 was a "single board" VME system... and as you say
you really couldn't add anything to it.
IIRC the only way to add anything to it was to pull the processor from its
socket, plug in a daughterboard, and then plug the processor back into that.
It did feel a whole lot more responsive with that extra 8MB of memory!
The method to "upgrade" a Sun-3/50 was to pull the gate arrays and add a
doughter board. There have been such extensions from "Sunflower". A company
that was latrer forced by Sun to rename into "Solflower".
Jörg
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EMail:joerg@schily.net (home) Jörg Schilling D-13353 Berlin
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