Asus Maximus II Gene - Manual (Page 39)

2.4 System memory
2.4.1 Overview
The motherboard comes with four Double Data Rate 2 (DDR2) Dual Inline Memory
Modules (DIMM) sockets.
A DDR2 module has the same physical dimensions as a DDR DIMM but is notched
differently to prevent installation on a DDR DIMM socket.
The figure illustrates the location of the DDR2 DIMM sockets:
Recommended memory configurations
One DIMM:
You may install one memory module in any slot as a single-channel operation.
Two DIMMs (dual-channel operation):
Four DIMMs (dual-channel operation):
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