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1.3.2 System Memory Interface
The (G)MCH integrates a system memory DDR2 controller with two, 64-bit wide interfaces.
Only Double Data Rate (DDR2) memory is supported; consequently, the buffers support only
SSTL_1.8 V signal interfaces. The memory controller interface is fully configurable through a set
of control registers. Features of the (G)MCH memory controller include:
 Maximum memory size:
 4 GB for 82945G GMCH and 82945P MCH
 2 GB for 82945GZ/82945GC GMCH and 82945PL MCH