You may have noticed some odd numbers popping up around Intel processors lately. Where did they come from? What is their purpose?

It used to be that you only needed to look at that plump, little number before the "GHz" to know which processor is the biggest and baddest. Today's technology, sporting different cache sizes and front side bus speeds, makes comparing processors harder.

For some time, Apple and AMD relied less on clockspeed and more on overall speed of the system to show the benefits of their technology. In 2001, at Macworld New York, Apple Senior VP of Hardware, Jon Rubinstein, first discussed what he termed the "Megahertz Myth," maintaining that overall system design and processor architecture were most important to real-world computer speed. This was viewed by some outside the Mac fan base as an excuse for lower PowerPC clockspeeds. Three years later, Intel announced that they will reverse 35 years of marketing clockspeed and begin using processor numbers as a way to compare processors within processor families.

What do Intel's new numbers mean? There are five aspects that define a processor number:

1. Architecture
2. Cache
3. Clock Speed
4. Front Side Bus
5. Other Intel Technologies

Architecture
This is the internal design of the processor. This may include different instruction sets or process technologies.

Cache
A small amount of high-speed memory that stores recently used information that can be retrieved faster than getting the information from RAM.

Clock Speed
The internal speed at which the processor works, measured in gigahertz.

Front Side Bus
The connecting path between the processor, RAM, and other critical components. Think of it as the nervous system of your computer.

Other Intel Technologies
This will include any future technologies Intel builds into their chips as their processors evolve.

Starting July '04, all new Intel processors will be named using a combination of processor family name, like "Intel® Pentium® 4 processor" and 3-digit processor number such as 7xx, 5xx, or 3xx.

Here's an example of a processor using the new naming system:

This number will be defined by Intel and you'll be able to compare processors within a processor family. For example, if Intel comes out with a Pentium 4 with better specs, its processor number would be higher than 560.

This doesn't mean that you can use the processor number to compare different processor families. For example, a Pentium M 755 and Pentium 4 755 may have very different physical characteristics and features.

Intel's numbering system will help compare processors within Intel processor families but it's of no use when trying to compare Intel processors to Apple or AMD processors... any more than using GHz.

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