Technical Reference; Memory Map; Addressable Memory; What This Chapter Contains 2.1 Memory Map - Intel BLKDG31GL Technical Product Specification

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Technical Reference

What This Chapter Contains
2.1 Memory Map................................................................................... 37
2.2 Connectors and Headers................................................................... 40
2.3 Jumper Block .................................................................................. 50
2.4 Mechanical Considerations ................................................................ 51
2.5 Electrical Considerations ................................................................... 52
2.6 Thermal Considerations .................................................................... 53
2.7 Reliability ....................................................................................... 55
2.8 Environmental ................................................................................ 55
2.1

Memory Map

2.1.1

Addressable Memory

The board utilizes 4 GB of addressable system memory. Typically the address space
that is allocated for PCI Conventional bus add-in cards, BIOS (SPI Flash), and chipset
overhead resides above the top of DRAM (total system memory). On a system that
has 4 GB of system memory installed, it is not possible to use all of the installed
memory due to system address space being allocated for other system critical
functions. These functions include the following:
• BIOS/SPI Flash (4 Mb)
• Local APIC (19 MB)
• Direct Media Interface (40 MB)
• Front side bus interrupts (17 MB)
• GMCH base address registers, internal graphics ranges
• Memory-mapped I/O that is dynamically allocated for PCI Conventional add-in
cards
NOTE
System resources and hardware (such as PCI) require physical memory address
locations that can reduce available addressable system memory. This could result in a
reduction of as much as 1 GB or more of physical addressable memory being available
to the operating system and applications, depending on the system configuration and
operating system.
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