Intel BLKDP67BG Technical Product Specification page 18

Intel Desktop Board DP67BG Technical Product Specification
Figure 3 illustrates the memory channel and DIMM configuration.
Figure 3. Memory Channel and DIMM Configuration
NOTE
The Intel Core i7, Intel Core i5, and Intel Core i3 processors require memory to be
populated in the DIMM 1 (Channel A, DIMM 0) socket.
For best memory performance always install memory into the blue DIMM memory
sockets if only installing two DIMMs in your configuration.
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