Intel Chipsets

You can't talk about chipsets today without discussing Intel because it currently owns the vast majority of the chipset market. It is interesting to note that we probably have Compaq to thank for forcing Intel into the chipset business in the first place!

The thing that really started it all was the introduction of the EISA bus designed by Compaq in 1989. At that time, it had shared the bus with other manufacturers in an attempt to make it a market standard. However, Compaq refused to share its EISA bus chipset—a set of custom chips necessary to implement this bus on a motherboard.

Enter Intel, who decided to fill the chipset void for the rest of the PC manufacturers wanting to build EISA bus motherboards. As is well known today, the EISA bus failed to become a market success except for a short-term niche server business, but Intel now had a taste of the chipset business and this it apparently wouldn't forget.

With the introduction of the 286 and 386 processors, Intel became impatient with how long it took the other chipset companies to create chipsets around its new processor designs; this delayed the introduction of motherboards that supported the new processors.

For example, it took more than two years after the 286 processor was introduced for the first 286 motherboards to appear and just over a year for the first 386 motherboards to appear after the 386 had been introduced.

Intel couldn't sell its processors in volume until other manufacturers made motherboards that would support them, so it thought that by developing motherboard chipsets for a new processor in parallel with the new processor, it could jumpstart the motherboard business by providing ready-made chipsets for the motherboard manufacturers to use.

Intel tested this by introducing the 420 series chipsets along with its 486 processor in April 1989. This enabled the motherboard companies to get busy right away, and in only a few months the first 486 motherboards appeared. Of course, the other chipset manufacturers weren't happy.

Now they had Intel as a competitor, and Intel would always have chipsets for new processors on the market first! Intel then realized that it made both processors and chipsets, which were 90% of the components on a typical motherboard.

What better way to ensure that motherboards were available for its Pentium processor when it was introduced than by making its own motherboards as well and having these boards ready on the new processor's introduction date.

When the first Pentium processor debuted in 1993, Intel also debuted the 430LX chipset as well as a fully finished motherboard. Now, besides the chipset companies being upset, the motherboard companies weren't too happy, either.

Intel was not only the major supplier of parts needed to build finished boards (processors and chipsets), but was now building and selling the finished boards as well. By 1994, Intel dominated the processor and chipset markets and had cornered the motherboard market as well.

Now as Intel develops new processors, it develops chipsets and motherboards simultaneously, which means they can be announced and shipped in unison. This eliminates the delay between introducing new processors and waiting for motherboards and systems capable of using them, which was common in the industry's early days.

For the consumer, this means no waiting for new systems. Since the original Pentium processor in 1993, we have been able to purchase ready-made systems on the same day a new processor is released. In my seminars, I ask how many people in the class have Intel-brand PCs.

Of course, Intel does not sell or market a PC under its own name, so nobody thinks they have an "Intel-brand" PC. But, if your motherboard was made by Intel, for all intents and purposes you sure seem to have an Intel-brand PC, at least as far as the components are concerned.

Does it really matter whether Dell, Gateway, or Micron put that same Intel motherboard into a slightly different looking case with their name on it? If you look under the covers, you'll find that many, if not most, of the systems from the major manufacturers are really the same because they basically use the same parts.

Although more and more major manufacturers are offering AMD Athlon- and Duron-based systems as alternatives to Intel's, no manufacturer dominates AMD motherboard sales the way Intel has dominated OEM sales to major system manufacturers.

To hold down pricing, many low-cost retail systems based on micro-ATX motherboards use non-Intel motherboards (albeit with Intel chipsets in most cases). But, even though many companies make Intel-compatible motherboards for aftermarket upgrades or local computer assemblers, Intel still dominates the major vendor OEM market for midrange and high-end systems.

Intel Chipset Model Numbers

Starting with the 486 in 1989, Intel began a pattern of numbering its chipsets as follows:

Chipset Number

Processor Family


P4 (486)


P5 (Pentium)


P6 (Pentium Pro/PII/PIII)


P6/P7 (PII/PIII/P4) with hub architecture


P6 server (Pentium Pro/PII/PIII Xeon)


Xeon workstation with hub architecture


Xeon server with hub architecture


Itanium processor


Itanium 2 processor with hub architecture

The chipset numbers listed here are abbreviations of the actual chipset numbers stamped on the individual chips. For example, one of the popular Pentium II/III chipsets was the Intel 440BX chipset, which consisted of two components: the 82443BX North Bridge and the 82371EX South Bridge.

Likewise, the 845 chipset supports the Pentium 4 and consists of two main parts, including the 82845 Memory Controller Hub (MCH; replaces the North Bridge) and an 82801BA I/O Controller Hub (ICH2; replaces the South Bridge).

By reading the logo (Intel or others) as well as the part number and letter combinations on the larger chips on your motherboard, you can quickly identify the chipset your motherboard uses.

Intel has used two distinct chipset architectures: a North/South Bridge architecture and a newer hub architecture. All its more recent 800 series chipsets use the hub architecture.