224
Upgrade and Maintenance Manual
CX270
S2
Main memory
7.1
Basic information
– Each CPU offers 8 Slots for DDR3 memory modules organized in 2 banks
and 4 channels
– If you need more than 8 slots you have to configure the 2nd CPU.
– Supported memory modules:
There are 3 different kinds of DDR3 Memory Modules available: UDIMM /
RDIMM and LRDIMM
– UDIMM / RDIMM / LRDIMM offer different functionality. Mix of UDIMM /
RDIMM / LRDIMM is not allowed.
– If 1.5V and 1.35V DIMMs are mixed, the DIMMs will run at 1.5V
– Depending on the amount of memory configured you can decide between 2
basic modes of operation: Independent and Performance mode.
– Max. DDR3 memory speed depends on the memory configuration on one
memory channel and the speed of the CPU.
– The memory channel with the lowest speed defines the speed of all CPU
channels in the system.
– If memory modules with different capacities are used: Populate modules
with higher capacities first.
– If memory modules with different speeds are used: Populate modules with
higher speed first.
– Populate same amounts of memory equally for both CPUs.
7.1.1
Memory sequence
– Populate memory slot 1 / channel A (DIMM-A1) first.
– Within the 4 channels, memory slot 1 must be populated prior to slot 2.
– If memory modules with different capacities are used:
– Install modules with higher capacities first.
– Within a channel, install modules in descending order of capacity.
– If memory modules with different speeds are used, the lowest clock rate
applies for all DIMMs.
