
Intel® Server Board SE7520AF2 TPS
Functional Architecture
Revision 1.2
71
Intel order number C77866-003
Figure 15. Intel® Xeon Processor Memory Address Space
3.5.1.1
DOS Compatibility Region
The first region of memory below 1 MB was defined for early PCs, and must be maintained for
compatibility. The region is divided into subregions as shown in the following figure.
4GB
Optional ISA Hole
Top of Low Memory (TOLM)
16MB
15MB
1MB
640KB
512KB
0
Additional Main
Memory Address
Range
Main Memory
Address Range
DOS Legacy
Address Range
Lo PCI Memory
Space Range
TSEG SMRAM
64GB
Hi PCI Memory
Address Range
Upper Memory
Ranges