[comp.sys.atari.st] RAM upgrade for 1040STf

knop@duteca (P. Knoppers) (06/26/89)

I want to increase the memory of my 1040STf to 2.5M.  I have
saved some articles about this subject, but all involve adding 
daughter boards or piggy-backing of chips.  This increases the
chipcount and the demands on the power supply.  Soldering on a 
daughter board makes repair very hard.  I would prefer to de-
solder one bank of RAM chips and replace them by sockets that 
will contain 1M bit chips.  I know that there are several types 
of motherboard in use in the 1040 STf.  Mine has the board with 
the RAM chips underneath the power supply.  There are in total 
32 RAM chips (256k bit each).

My problem is, that I do not know which 16 RAM chips I should 
replace. I have also found a solder blob that is marked 256k 
and 1M (or something similar).  I suppose that I have to change 
this too. 
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P. Knoppers, Delft Univ. of Technology, The Netherlands, knop@duteca.tudelft.nl