450NX Datasheet, PDF (9/248 Pages) Intel Corporation – Intel 450NX PCIset

Introduction ₁
1.1
Overview
The Intel^® 450NX PCIset provides an integrated Host-to-PCI bridge and memory controller
optimized for multiprocessor systems and standard high-volume (SHV) servers based on the
Pentium^® II Xeon™ processor variant of the P6 family. The Intel 450NX PCIset consists of four
components: 82454NX PCI Expander Bridge (PXB), 82451NX Memory and I/O Bridge
Controller (MIOC), 82452NX RAS/CAS Generator (RCG), and 82453NX Data Path
Multiplexor (MUX). Figure 1-1 illustrates a typical SHV server system based on the Intel
450NX PCIset. The system bus interface supports up to 4 Pentium II Xeon processors at 100
MHz. An additional bus mastering agent such as a cluster bridge can be supported at reduced
frequencies. Two dedicated PCI Expander Bridges (PXBs) can be connected via the Expander
Optional
Cluster
Bridge
L2
Cache
Pentium® II
Xeon™
processor
L2
Cache
Pentium II
Xeon
processor
System Bus
third-party
controls
MIOC
Memory
and I/O
Controller
MD[71:0]
MA[13:0]
Control
L2
Cache
Pentium II
Xeon
processor
MUXs
L2
Cache
Pentium II
Xeon
processor
AGTL+ 100 MHz
Memory
Subsystem
1 or 2 cards
Expander
Buses
X1
X0
PXB #1
PCI
Expander
Bridge
PXB #0
PCI
Expander
Bridge
1B 1A 0B 0A
PIIX4E
South Bridge
BMIDE HDDs
USB ^USB
IDE CD-ROM
PCI
Slots
I/O
APIC _XCVR
ISA slots
4 PCI Buses
32-bit, 33 MHz, 3.3v or 5v
Can link pairs into 64-bit bus
BIOS
Flash
EPROM
KBC
SIO
8042
Figure 1-1: Simplified Intel^® 450NX PCIset System Block Diagram
Intel® 450NX PCIset
1-1