Re: New kid on the block, seeking advice...

[mjmahon@aol.com (Michael J. Mahon)]

Ernest replied:

>"Michael J. Mahon" <mjmahon@aol.com> wrote in message
>20030605180704.00333.00000071@mb-m12.aol.com">news:20030605180704.00333.00000071@mb-m12.aol.com...
>> Andrea asked:
>>
>> >1) The memory expansion has a DIL16 terminated flat cable which is
>> >unplugged. I remember replacing a socketed TTL somewhere on the
>> >mainboard with this cable, but I don't remember which. Any hint?
>
>> The answer is into _any_ DRAM chip socket, so pick the one that
>> is most convenient when the card is in slot 0.
>
>Really? I didn't know that the cable could plug into any of the sockets. I
>never have seen any directions on how to install a memory card but since I've
>only ever seen them plugged into the first socket, I assumed that that was
>where they had to go.

Hi, Ernest!  ;-)

That is the usual chip, given the medium length of the card and its
usual placement in slot 0.  But RAM cards can be used in other
slots, making other DRAMs more convenient.

The only signals that the card gets from the DRAM pigtail are
RAS and CAS, which are identical on all main board DRAM chips.
These signals are a little more complex to generate on the card,
given the available slot timing signals, so the first RAM card design
just stole them from the main board.  ;-)

Later (larger) RAM cards generate RAS and CAS on board, so no
pigtail is needed.

-michael

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