14 Sep
2005
14 Sep
'05
4:03 p.m.
Later, they switched to one row of 64K DRAMs soldered
in, with sockets for
another three rows. Some (all?) of those motherboards could be trivially
modified to take 2 rows of 64K plus two rows of 256K.
I can't rememebr if the PC 64K to 256K board has the socket for the extra
address mux chip, etc, but I think it doesn't.
All IBM PC/XT boards that I've seen can be modified to take 2 rows of
256K chips. And on all the boards I've seen, all 4 rows of RAM are
socketed, so it's easy to replace rows 0 and 1 with said 256K chips. Then
just plug in the 'S158 (or 'F158), solder the jumper and go.
-tony