NCR PC4I, Owner'S Manual

Page: 71 / 167

OPTIONS INSTALLATION
Expansion I.C.s Light Pen
Expanded Memory
You can increase the system memory in two ways:
1. You can add 256KB chips, or 256KB and 64KB chips, on the MPB
in the empty slots to bring your memory capacity up to 448 KB,
512 KB, 576 KB, or 640 KB.
2. You can purchase an expansion board and add chips in incre­
ments of 64 KB up to a system maximum of 640 KB. (NOTE: The
MPB must contain sufficient chips to total exactly 256KB before a
memory expansion board can be added.)
The MPB in your computer contains one of the following combina­
tions of chips. You can add 256 KB chips and 64 KB chips in the empty
slots, or substitute 256 KB chips for two banks of 64 KB chips if your
computer is presently equipped with 64 KB chips, to bring your total
memory capacity to 640 KB.
Bank 0 Bank 1 Bank 2 Bank 3 Total
64
64 64 64
256
256 0 0
0 256
OWNER’S MANUAL
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