Cisco UCS B200 M3 Installation And Service Note page 27

The figure below shows a logical view of the DIMMs and channels.
Figure 20: Logical Representation of DIMMs and Channels
DIMMs can be used in the blade server in a one DIMM per Channel (1DPC) configuration, in a two DIMMs per Channel (2DPC)
configuration, or a three DIMMs per Channel (3DPC) configuration.
Each CPU in a Cisco UCS B200 M3 blade server supports four channels of three memory slots each. In a 1 DPC configuration,
DIMMs are in slot 0 only. In a 2 DPC configuration, DIMMs are in both slot 0 and slot 1. In a 3 DPC configuration, DIMMs are in
slot 0, slot 1, and slot 2.
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