AC82G41SLGQ3 Datasheet, PDF (55/604 Pages) Intel Corporation – Intel® 4 Series Chipset Family

System Address Map
5. The only peer-to-peer cycles allowed below the top of Low Usable memory (register
TOLUD) are DMI Interface to PCI Express VGA range writes. Note that peer to peer
cycles to the Internal Graphics VGA range are not supported.
Figure 5 represents system memory address map in a simplified form.
Datasheet
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