Dell POWEREDGE 1855 - Manual (Page 58)

The following procedures describe how to remove and install the following components:
l Memory modules
l Daughter cards
l Microprocessors
l Server module battery
l Hard drives
Memory
The six memory module sockets can accommodate from 512 MB to 16 GB of registered ECC PC2-3200 (DDR 2 400) memory. The memory sockets are located
near the back of the server module board. See
Figure A -3 in "Server Module Board Connectors."
You can upgrade the system memory by installing combinations of 256-MB, 512-MB, 1-GB, 2-GB, or 4-GB registered low-profile memory modules. You can
purchase memory upgrade kits from Dell.
The memory module sockets are arranged in three banks on two channels (A and B). The memory module banks are identified as follows:
l Bank 1: DIMM1_A and DIMM1_B
l Bank 2: DIMM2_A and DIMM2_B
l Bank 3: DIMM3_A and DIMM3_B
See Figure A -3 for the locations of the memory sockets and banks on the server module board.
General Memory Module Installation Guidelines
l A single-memory module configuration is not supported.
l If two or more memory modules are installed, they must be installed in pairs of matched memory size, speed, and technology.
l Install memory modules in order of decreasing capacity, beginning with bank 1, then bank 2, and then bank 3.
l The system supports both single-ranked and dual-ranked memory modules.
Memory modules marked with a 1R are single ranked and modules marked with a 2R are dual ranked.
l If you install both single-ranked and dual-ranked memory modules, the dual-ranked memory modules must be installed in bank 1, regardless of
capacity.
l Dual-ranked memory modules are not supported in bank 3.
Table 6 -1 and Table 6 -2 show examples of different memory configurations. Table 6 -2 lists the various allowable combinations of single- and dual-ranked
memory modules.
Table 6-1. Sample Memory Configurations
NOTICE: If you remove your original memory modules from the system during a memory upgrade, keep them separate from any new memory modules
that you may have, even if you purchased the new memory modules from Dell. Use only registered ECC DDR II memory modules.
NOTE: A single-memory module configuration is not supported, and the maximum memory configuration depends on the availability of single-rank 2-GB
memory modules.
NOTE: The memory modules must be PC2-3200 compliant.
NOTE: Dual-rank memory modules with less capacity take precedence over single-ranked memory modules with greater capacity.
Total Memory DIMM1_A DIMM1_B DIMM2_A DIMM2_B DIMM3_A DIMM3_B
512 MB 256 MB 256 MB none none none none
1 GB 256 MB 256 MB 256 MB 256 MB none none
1 GB 512 MB 512 MB none none none none
2 GB 512 MB 512 MB 512 MB 512 MB none none
2 GB 1 GB 1 GB none none none none
3 GB 1 GB 1 GB 512 MB 512 MB none none
3 GB 512 MB 512 MB 512 MB 512 MB 512 MB 512 MB
4 GB 1 GB 1 GB 1 GB 1 GB none none
4 GB 1 GB 1 GB 512 MB 512 MB 512 MB 512 MB
6 GB 2 GB 2 GB 1 GB 1 GB none none
6 GB 1 GB 1 GB 1 GB 1 GB 1 GB 1 GB
8 GB 2 GB 2 GB 2 GB 2 GB none none