abc@adm.BRL.MIL (Brinton Cooper) (06/01/90)
I purchased a QUADMEG-AT (128K) memory board for an old-ish IBM-PC/AT.
The board was designed for the 4.77 MHz machine. However, it turns out
that this machine contains a 12 MHz crystal.
(To justify my stupidity, let me point out that this machine belongs
to a nearby school for whom I'm doing a 'volunteer' project. I planned
to donate the board.)
The specific problem is that the machine does not "see" the memory on a
cold boot; it gives a diagnostic of the form:
080042 AA00 Memory Error 201
which appears during memory check after machine has indicated that 512K
is OK.
The (64K) memory chips in the QUADMET board are 150 ns Fujitsu chips
(MB8264A-15); these are 16pin chips.
For those of you who know this product:
1. Can I get reliable operation by changing the memory chips?
2. Is it only the chip speed that is likely to limit things?
3. I have only a JAMECO catalog here at the moment, and the only
faster chip of the correct configuration is a 100 ns model. Is
something even available that will work?
4. If nothing will make this board work reliably in this
machine, what am I offered for the board?
Other advice appreciated, including pointers to boards that will work
and that don't cost an arm and a leg. I'll entertain buying a used
board from you.
In view of the large number of articles posted to these groups and the
probable lack of general interest in this topic, you might wish to
e-mail your responses to me.
_Brint Cooper
H: 301-879-8927
W: 301278-6883
<abc@brl.mil>
--
_Brinton Cooper BRL - Where "Research" is our Middle Name.