Technical Reference

2.2.2Memory Map

Table 11 lists the system memory map.

Table 11. System Memory Map

Address Range (decimal)

Address Range (hex)

Size

Description

 

 

 

 

1024 K - 4194304 K

100000 - FFFFFFFF

4095 MB

Extended memory

 

 

 

 

960 K - 1024 K

F0000 - FFFFF

64 KB

Runtime BIOS

 

 

 

 

896 K - 960 K

E0000 - EFFFF

64 KB

Reserved

 

 

 

 

800 K - 896 K

C8000 - DFFFF

96 KB

Potential available high DOS

 

 

 

memory (open to the PCI

 

 

 

Conventional bus). Dependent on

 

 

 

video adapter used.

 

 

 

 

640 K - 800 K

A0000 - C7FFF

160 KB

Video memory and BIOS

 

 

 

 

639 K - 640 K

9FC00 - 9FFFF

1 KB

Extended BIOS data (movable by

 

 

 

memory manager software)

 

 

 

 

512 K - 639 K

80000 - 9FBFF

127 KB

Extended conventional memory

 

 

 

 

0 K - 512 K

00000 - 7FFFF

512 KB

Conventional memory

 

 

 

 

2.3 DMA Channels

Table 12. DMA Channels

DMA Channel Number

Data Width

System Resource

 

 

 

0

8 or 16 bits

Open

 

 

 

1

8 or 16 bits

Parallel port

 

 

 

2

8 or 16 bits

Diskette drive

 

 

 

3

8 or 16 bits

Parallel port (for ECP or EPP)

 

 

 

4

8 or 16 bits

DMA controller

 

 

 

5

16 bits

Open

 

 

 

6

16 bits

Open

 

 

 

7

16 bits

Open

 

 

 

57

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Intel D925XBC, D925XCV specifications DMA Channels, System Memory Map

D925XBC, D925XCV specifications

The Intel D925XBC and D925XCV are motherboards designed for Intel's LGA 775 socket, targeted primarily at the desktop market during the mid-2000s. These motherboards support Intel's innovative 800 MHz Front Side Bus and provide a robust platform for various computing applications, including gaming and multitasking.

One of the standout features of the D925XBC and D925XCV is their compatibility with Intel's Pentium 4 and Pentium D dual-core processors. These processors deliver impressive performance, especially for users engaging in demanding tasks such as video editing and 3D rendering. The support for dual-channel DDR2 memory allows for increased bandwidth and improved overall system performance, accommodating up to 8 GB of memory in total.

The motherboards are equipped with the Intel 925X chipset, which integrates advanced technologies. This chipset supports Intel's Enhanced Memory 64 Technology (EM64T), allowing for more efficient processing power and better resource management. The presence of the I/O Controller Hub (ICH6) also enhances connectivity options, including SATA 3.0 Gbps interfaces for faster data transfer rates and improved storage capabilities.

Regarding expansion and connectivity, both motherboards feature multiple PCI Express slots along with PCI slots, allowing users to customize their systems according to their needs. This expandability is essential for gamers and professionals looking to add advanced graphics cards and other peripherals. Additionally, these boards come with integrated audio, ensuring satisfactory sound quality without the need for additional sound cards.

The D925XBC and D925XCV motherboards also include integrated Ethernet controllers, supporting fast network connectivity essential for gaming and high-speed internet access. With multiple USB ports available, users can connect a wide variety of devices easily, enhancing the flexibility of their setups.

In terms of form factor, both boards follow the ATX layout, providing compatibility with a broad range of computer cases. This ensures ease of installation and upgrades while promoting good airflow and optimal thermal management for the components installed.

Overall, the Intel D925XBC and D925XCV motherboards integrate essential features and technologies that provide a solid foundation for desktop computing during their time. With strong processing capabilities, expandability, and good connectivity options, these boards were well-received by users looking for reliable performance and versatility in their systems.