>> Question1: Will Netbsd work on this system?

Well...FSVO "work".  I wouldn't want to try to do anything significant
in 4M.  (And yes, port-sun3 is really the correct place to ask.  Note
Cc: and Reply-To:.)

>> Question3: Will it be powerful enough to run X, as well as working
>> as a basic Sendmail/Pop3 server for 3 users

My guess is, probably not, unless you have the third-party RAM upgrade.
If you really do have only 4M, go with the oldest OS you can possibly
stand to run - the newer it is, the bigger it is, in general; stripping
everything unnecessary out helps, but the newer OSes are still usually
bigger than the older ones.

>> (I don't know how much RAM is in this thing, but is processor speed
>> an issue assuming there's enough RAM)?

> Probably 4M.  These machines were sold in fixed configuration, and
> there was no way to add RAM from Sun.  There was third-party RAM
> upgrade available, though.  I think it was by removing the RAM chips
> from the motherboard and pluggin in a dauther board in place.

I saw one once that had an upgrade installed.  It wasn't done by
removing the RAM; the RAM was soldered in place.  It was done by
pulling two of the large chips - memory controller, I think, and one
other.  (MMU maybe?)  The daughterboard plugged into those two sockets
and had two sockets for the chips to get moved into, plus some SIMM
sockets and I think a little additional logic.

Of course, there may be multiple variants of the -3/50 memory upgrade
kit; I've seen only the one example.

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