Fujitsu PRIMERGY RX1330 M1

208 Upgrade and Maintenance Manual RX1330 M1
Main memory
10.1.1.2 Modes of operation
Figure 138: Dual-channel symmetric and asymmetric mode
– The maximum performance can be achieved in a symmetric dual-channel
configuration. Therefore both channels have to be populated with the same
amount of memory. The DRAM device technology (1Gbit / 2Gbit / 4Gbit)
may vary from one channel to the other.
– If the amount of memory differs between the two channels, the system board
will run in dual-channel asymmetric mode.
– Regardless of the mode, all DIMMs will run at the highest common
frequency that is allowed by the SPD Data of the DIMMs and the max. speed
of the selected configuration.
– Single-channel mode is used when 1 memory module is populated in
DIMM 1A.
channel
A B
Dual mode
Memory size
channel
AB
Dual mode Single
mode
Dual-channel symmetric mode Dual-channel asymmetric mode
Memory size A
Memory size B