Three Dimms; Example Dual Channel Memory Configuration With Four Dimms; Example Dual Channel Memory Configuration With Three Dimms - Intel DH55HC Product Manual

Intel Desktop Board DH55HC Product Guide
Figure 15. Example 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 16).
Figure 16. Example Dual Channel Memory Configuration with Three DIMMs
NOTE
All other memory configurations will result in single channel memory operation.
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