Configuring and using DDR3 memory with HP ProLiant Gen8 Servers

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Figure 9. Throughput at different DIMM speeds with 1 DIMM per channel using 16GB 1600 RDIMMs.
Number of DIMMs per channel and throughput
Figure 10 shows the measured memory throughput for several one and two DIMM per channel configurations.
Throughput actually decreases when a second DIMM is added to each channel. With 2 DIMMs per channel installed, the
memory controllers use more of the command bus bandwidth issuing refresh cycles to the additional ranks on each
channel. This reduces the command bus bandwidth that is available to issue read and write requests and thus causes a
reduction in overall throughput. Application workloads that are more sensitive to memory capacity than throughput will
still benefit from the second DIMM on each channel.
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800 MT/s 1066 MT/s 1333 MT/s 1600 MT/s
Memory throughput as a function of Memory Speed
(Using 8 x 16GB 2R 1600 RDIMMs at 1 DIMM per channel)
GB/s Throughput