AT&T 3B2/300 Technical Reference Manual page 144

EQUIPMENT D E S C R I P T I O N - - - - - - - - - - - - - - - - - - - - - - - - - - -
RAM Equipage Considerations
Version 3 computers may be equipped with as much memory as the backplane will allow.
However, Version 2 computers have certain considerations that must be followed.
The 1- and 2-megabyte cards can be equipped in the same machine; however, the 2-megabyte card
must be in connector MO. Four-slot computers (3B2/300 and 3B2/310) equipped with power supplies
having a red ON/STANDBY switch are limited to 2 megabytes of RAM. To expand these machines to
3 or 4 megabytes of RAM requires the replacement of the power supply. Only early production units
are equipped with power supply units having a red ON/STANDBY switch. The following table
summarizes the equipage of RAM cards in Version 2 computers.
RAM CARD CONFIGURATION SUMMARY
MEMORY SIZE MO CONNECTOR Ml CONNECTOR
0.5 MEGABYTES 0.25-MEGABYTE CARD 0.25-MEGABYTE CARD
(382/300, only)
1.0 MEGABYTES
I-MEGABYTE CARD
-
2.0 MEGABYTES I-MEGABYTE CARD I-MEGABYTE CARD
2.0 MEGABYTES 2-MEGABYTE CARD
-
3.0 MEGABYTES
2-MEGABYTE CARD I-MEGABYTE CARD
4.0 MEGABYTES 2-MEGABYTE CARD 2-MEGABYTE CARD
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