Specifications

CHAPTER 4
Expansion Features
RAM DIMMs 43
The 8-byte DIMMs can be installed one or more at a time. The Macintosh Performa 6400
computer supports only linear memory organization, therefore no performance gains are
seen when two DIMMs of the same size are installed. Any size DIMM can be installed in
either DIMM slot, and the combined memory of all of the DIMMs installed will be
configured as a contiguous memory space.
RAM DIMM Connectors 4
Table 4-2 gives the pin assignments for the RAM DIMM connectors.
Table 4-2 Pin assignments on the RAM DIMM connectors
Pin number Signal name Pin number Signal name
1 VSS 85 VSS
2 DQ(0) 86 DQ(32)
3 DQ(1) 87 DQ(33)
4 DQ(2) 88 DQ(34)
5 DQ(3) 89 DQ(35)
6 VCC 90 VCC
7 DQ(4) 91 DQ(36)
8 DQ(5) 92 DQ(37)
9 DQ(6) 93 DQ(38)
10 DQ(7) 94 DQ(39)
11 Reserved 95 Reserved
12 VSS 96 VSS
13 DQ(8) 97 DQ(40)
14 DQ(9) 98 DQ(41)
15 DQ(10) 99 DQ(42)
16 DQ(11) 100 DQ(43)
17 DQ(12) 101 DQ(44)
18 VCC 102 VCC
19 DQ(13) 103 DQ(45)
20 DQ(14) 104 DQ(46)
21 DQ(15) 105 DQ(47)
22 Reserved 106 Reserved
23 VSS 107 VSS
continued