5 Configuring and Upgrading DRAM
Memory
For higher system speed or greater throughput, DRAM memory can be upgraded
either by replacing SIMMs with those of greater size, or by widening the memory
bus from 128 bits to 256 bits by adding more SIMMs.
Note:
When configuring or upgrading DRAM, the following rules must be
observed:
•
•
5.1 Configuring DRAM Memory
Table 22 lists the DRAM memory configurations available. Refer to Figure 1 for
SIMM connector location.
Table 22 AlphaPC 164 DRAM Memory Configurations
Total Memory
16MB
32MB
64MB
128MB
256MB
Total Memory
32MB
64MB
128MB
256MB
512MB
All SIMMs must be 36-bit and have a 70-ns or faster access time.
All SIMMs must be of equal size.
128-Bit Memory Mode (J1 In)
J5 Through J8 Populated
with SIMM Sizes...
1Mb
36
X
2Mb
36
X
4Mb
36
X
8Mb
X
36
16Mb
X
36
256-Bit Memory Mode (J1 Out)
J5 Through J12 Populated
with SIMM Sizes...
1Mb
36
X
2Mb
36
X
4Mb
36
X
8Mb
X
36
16Mb
X
36
Configuring and Upgrading DRAM Memory
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