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Main memory controller, Dram interface – HP XU800 User Manual

Page 39

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39

2 System Board

Memory Controller Hub (8240)

AGP PCI Bus
Implementation

Main Memory Controller

The main memory controller is integrated in the MCH supporting two
primary rambus channels (A and B).

DRAM Interface

The MCH provides optional Host bus error checking for data, address,
request and response signals. Only 300 MHz and 400 MHz Direct Rambus
devices are supported in any of 64, 128 or 256 Mb technology. 64 and 128
MBit RDRAMs use page sizes of 1 kbytes, while 256 Mb devices target
1 kbyte or 2 kbyte pages.

A maximum number of 64 Rambus devices (32 devices maximum per
channel) is supported. Both channels must be populated with paired
memory modules.

Pentium III Processor

GX-Device 1
AGP Port
Interface

PCI-to-PCI

Device 0

I840

Memory

Controller Hub

(MCH)

Universal

AGP
PRO

Connector

AGP

4x Bus

(133 MHz)

Hub Link 8-bit

PCI-to-PCI

Two PCI

64-bit 66

MHz slots

PCI 64-bit 66 MHz
Hub (P64H)

I/O Controller
Hub (ICH)

Hub Link 16-bit

PCI-to-PCI