Three Dimms; Dual Channel Memory Configuration With Four Dimms; Dual Channel Memory Configuration With Three Dimms - Intel DP43BF Product Manual

Installing and Replacing Desktop Board Components
If additional memory is to be used, install another matched pair of DIMMs in DIMM 1
(black) in channels A and B (see Figure 14).
Figure 14. Dual Channel Memory Configuration with Four DIMMs

Three DIMMs

If you want to use three DIMMs in a dual-channel configuration, install a matched pair
of DIMMs equal in speed and size in the DIMM 0 (blue) socket of channel A and the
DIMM 0 (blue) socket of channel B. Install the third DIMM in the DIMM 1 (black)
socket of either channel A or channel B (see Figure 15).
Figure 15. Dual Channel Memory Configuration with Three DIMMs
NOTE
All other memory configurations will result in single channel memory operation.
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