Intel Pentium Extreme Edition 955 & 975X Express Chipset: 65nm is Here

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The D975XBX & 975X Express Chipset

To test the Pentium Extreme Edition 955 processor, Intel supplied us with one of their new D975XBX motherboards, which is based on the recently released 975X Express chipset. Unlike previous Intel desktop motherboards though, the D975XBX is loaded with "enthusiast" oriented features that give user's the ability to alter voltages and bus speeds, to easily overclock the CPU. Take a look - this isn't a motherboard you'd expect to come directly from Intel.

The D975XBX & 975X Express Chipset
Multi-GPU Support & More
·_Support for Intel Pentium Processor Extreme Edition (LGA775 / 800MHz system bus)
·_Support for Intel Pentium 4 Processor Extreme Edition supporting Hyper-Threading Technology (LGA775 / 1066MHz system bus)
·_Support for Intel Pentium D Processor (LGA775 / 800MHz system bus)
·_Support for Intel Pentium 4 Processor supporting Hyper-Threading Technology (LGA775 / 800MHz system bus)

·_Four 240-pin DDR2 SDRAM Dual Inline Memory Module (DIMM) sockets
·_Support for 667 and 533 MHz DDR2 DIMMs
·_Support for up to 8 GB of system memory
·_Support for ECC and non-ECC memory

·_Intel 975X Express Chipset

I/O Control
·_Legacy I/O controller for diskette drive, serial, parallel, and PS/2 ports

·_Intel High Definition Audio subsystem
LAN Support
·_Gigabit (10/100/1000 Mbits/sec) LAN subsystem using the Intel 82573E/82573L Gigabit Ethernet Controller

Peripheral Interfaces
·_Eight USB 2.0 ports
·_One serial port
·_One parallel port
·_Four Serial ATA interfaces with RAID support
·_One parallel ATA IDE interface with UDMA 33, ATA-66/100 support
·_One diskette drive interface
·_PS/2 keyboard port
_PS/2 mouse port

Expansion Capabilities
·_Two PCI Conventional bus add-in card connectors (SMBus routed to both PCI Conventional bus add-in card connectors)

·_One Primary PCI Express x16 (electrical x16 or x8) bus add-in card connector

·_One Secondary PCI Express x16 (electrical x8) bus add-in card connector

·_One PCI Express x16 (electrical x4) bus add-in card connector

The D975XBX's features and specifications read like some of the enthusiast-class boards that come from partners like Asus or Abit. The board features three physical PCI Express X16 slots (with varying electrical connections) and supports ATI's CrossFire multi-GPU technology. NVIDIA's SLI technology isn't support just yet, however. Perhaps NVIDIA will enable SLI in a future driver release. By simply inserting a second video card, the first and second PEG slots' PCI Express lane configuration is automatically changed to a 8x8 configuration.

The D975XBX has a 5-phase power array and each FET in the array is adorned with a relatively large aluminum "flame" heatsink. And the Northbridge and Southbridge are also equipped with their own aluminum heatsinks as well. Four of the board's SATA ports are controlled by the ICH7R Southbridge and the other four by a Silicon Image controller. Its got 4 DDR2 DIMM slots, Gigabit Ethernet, and HD Audio support courtesy of a Sigmatel CODEC.


We snapped a couple of pictures of the D975XBX's BIOS to show off the main menu and some of the board's overclocking features. Intel does incorporate a few disclaimers, and buries the menu a few levels deep in the Advanced portion of the system setup section of the BIOS, but the overclocking features are there. As you can see, the CPU's multiplier can be altered, as can the front side bus speed, and numerous voltages.

At the hearts of the D975XBX motherboard is Intel's 975X Express chipset. The 975X Express is very similar to the older 955, but the 82975X Northbridge that's part of chipset has a more flexible PCI Express lane configuration. The 975X Express chipset supports all Intel LGA755 processors with 800MHz / 1066MHz bus speeds, and supports up to 8GB of DDR2-533 or DDR2-667 RAM (with or without ECC). The memory controller also incorporates Intel's "Memory Pipeline Technology" which accelerates transfers between the system memory and CPU.

The second component in the 975X chipset, the ICH7R Southbridge, has full support for Intel's Matrix Storage Technology (RAID 0, 1, 5, and 10), Intel Active Management Technology, and High Definition audio. The ICH7R is also equipped with 8 USB 2.0 ports, and Intel PRO/1000 Gigabit LAN support.

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