I have Allegro C3600 that unfortunately refuses to boot:
When it was sold to me, it was said not to have memory, what was
indicated at boot-up ("no memory found" on LCD). I was surprised to
discover though that there was 1 GB (?) DIMM in wrong socket. After
moving it to first one, the machine now halts with "dup entry in PDT"-
which might indicate that the DIMM is in deed faulty (or- how to check
further?). After a while got two 256MB RAM modules and the thing still
doesn't fire up.

When I put any of the DIMMs in socket 0, the machine will complain
about replacing DIMM00, when in 1, DIMM01 (so it sees them, but it
does with all three I have, two are taken from a working machine).
When I'm seating them in sockets 2 and on, it will say "no memory

I can't get to console neither on graphics nor serial port, too.

Does that mean the mainboard is damaged? Any solutions are