Datasheet

Sun Microsystems, Inc.

Figure 2-3: Intel vs. Opteron Architectures

I/O Expansion Capability to High-Speed Industry Buses

The traditional Northbridge/Southbridge architecture is not intended to support more than two core-logic elements. Adding addi-

tional high-speed functionality (such as Gigabit Ethernet, PCI-E, the InfiniBand Architecture, or any combination thereof) would have

to occur in one of three ways:

• The functionality would have to be attached to an existing bus interface such as the PCI bus. However, an existing bus may

not have sufficient bandwidth to support high-speed technologies, especially in instances in which multiple buses or

combinations of buses must be supported simultaneously.

• The functionality would have to be directly attached to the higher speed proprietary chip-to-chip interconnect bus via a

bridging device. However, the proprietary nature of this solution may limit the number of components available from

vendors, thus impacting cost and availability.

• The functionality would have to be integrated into one of the core logic components. This solution is the least flexible, as a

wide range of components would have to be created for each desired combination of feature-set buses.

18 of 45

DDR2

10.7 GB/s

DDR2

10.7 GB/s

FSB FSB

CPU

MCH

(Northbridge)

ESB-2

(Southbridge)

8 GB/s

CPU

I/O I/O

FBDIMM

Intel Architecture Sun Fire X4100 M2 / X4200 M2