82845PE Datasheet, PDF (15/176 Pages) Intel Corporation – 82845GE Graphics and Memory Controller Hub (GMCH) and 82845PE Memory Controller Hub (MCH)

Introduction
1.3
Intel^® 845GE / 845PE Chipset System Overview
Figure 1-1 shows an example block diagram of an 845GE/845PE chipset-based platform. The
845GE/845PE chipsets are designed for use in a desktop system based on an Intel^® Pentium^® 4
processor in a 478-pin package. The 845GE/845PE chipsets support the Pentium 4 processor with
256-KB L2 cache and the Pentium 4 processor with 512-KB L2 cache on 0.13 micron process. The
processor interface supports the Pentium 4 processor subset of the Extended Mode of the Scalable
Bus Protocol. In an 845GE/845PE chipset-based platform, I/O functions are integrated onto the
ICH4.
The 845GE chipset platform supports either an integrated graphics device (IGD) or an external
graphics device on AGP. The IGD has 3D, 2D, and video capabilities. The IGD also has two
multiplexed Intel DVO ports to support DVO devices. The GMCH’s AGP interface supports 1X/
2X/4X AGP data transfers and 2X/4X AGP Fast Writes, as defined in the Accelerated Graphics
Port Interface Specification, Revision 2.0 for 1.5 V signaling.
The 845PE chipset platform does not contain an integrated graphics device. Graphics is supported
with an external graphics device on AGP. The AGP interface has the same characteristics as the
845GE chipset.
The 845GE/845PE chipset platforms support 2 GB of system memory. The memory can be either
266/333 MHz Double Data Rate (DDR) memory components with a 64-bit wide data bus.
Available bandwidth is 2.7 GB/s using DDR333.
Section 1.4 provides an overview of the (G)MCH. The following sub-section provides an overview
of the ICH4.
Intel^® 82801DB I/O Controller Hub 4 (ICH4)
The ICH4 is a highly integrated multifunctional I/O Controller Hub that provides the interface to
the PCI Bus and integrates many of the functions needed in today’s PC platforms. The (G)MCH
and ICH4 communicate over a dedicated hub interface. The 82801DB ICH4 functions and
capabilities include:
• PCI Rev 2.2 compliant with support for 33 MHz PCI operations
• Supports up to six Request/Grant pairs (PCI slots)
• Power management logic support
• Enhanced DMA controller, interrupt controller, and timer functions
• Integrated IDE controller; Ultra ATA/100/66/33
• USB host interface; three host controllers and supports six USB ports; includes a EHCI high-
speed 2.0 USB controller
• Integrated LAN controller
• System Management Bus (SMBus) compatible with most I²C devices; ICH4 has both bus
master and slave capability
• AC ’97 2.3 supported for audio and telephony codecs; up to six channels
• Low Pin Count (LPC) interface
• FWH Interface (FWH Flash BIOS support)
• Alert on LAN* (AOL and AOL2)
Intel^® 82845GE/82845PE Datasheet
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