Intel DG33BU specifications Memory Map, Addressable Memory

2 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	56

2.1Memory Map

2.1.1Addressable Memory

The board utilizes 8 GB of addressable system memory. Typically the address space that is allocated for PCI Conventional bus add-in cards, PCI Express configuration space, BIOS (SPI Flash), and chipset overhead resides above the top of DRAM (total system memory). On a system that has 8 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 (8 Mbits)

•Local APIC (19 MB)

•Digital Media Interface (40 MB)

•Front side bus interrupts (17 MB)

•PCI Express configuration space (256 MB)

•GMCH base address registers, internal graphics ranges, PCI Express ports (up to 512 MB)

•Memory-mapped I/O that is dynamically allocated for PCI Conventional and PCI Express add-in cards

•Intel Management Engine support (6 MB)

•Base graphics memory support (1 MB or 8 MB)

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