May i know what does 'CPU stepping' means? It often comes across books, but i do not understand the function of it. Secondly, i would also like to clarify a few technicalities:

1. Core speed - is it the speed at which the processor is churning data in and out?
2. Mulitplier - either a hardware or BIOS configurable parameter to increase or decrease the processor's processing speed?
3. Bus speed - is it the rate of the bus how much pipelines(width) are there to process the data exchange between Northbridge and processor?
Rated FSB - is it the maximum speed the FSB is able to achieve?

Hope someone can enlighten me thank you.

Stepping referes to introduction or revision of the lithographic mask or masks within the set of plates that generate the patterning that produces the CPU. It goes hand in hand with the fact that they call the equipment that exposes the photo-resist to light 'Steppers'.

Steppers are basically the same as the optical film developing equipment used in old fashioned (by today's standards) 35mm film cameras. You have a negative that you shine light through, and the image of the negative is transposed to the substrate with different degrees of shrinkage or magnifications.

Typically, when a company such as Intel or AMD expend the money to do a stepping (i.e. a revision to the masks), they have found bugs in the logic or have engineered slightly different geometries that make the transistor or have found a slightly better way of wiring things up. In most cases, a stepping is generated to improve the product in some fashion, either to address concerns that will increase yield, fix logic bugs, or help improve the bin splits (i.e. create faster transistors hence faster CPUs), it could be done for one or more of these reasonse combined. Why Intel or AMD would generate a new stepping is really only known to them, what we observe is that some steppings alter the CPU enough that it overclocks better than others.

This is because various factors influence the switching speed or gate delay of the transistors that make the CPU, such as source-drain distance which is called gate length (or Lg). Other factors may be maskings for impants, changing the implant doping profiles which could help increase the switching speed and lead to a higher Fmax (maximum frequency).

It is not atypical for a specific stepping to change the maximum clockspeed, thus you will see many 'professional' overclockers discussing various steppings.

Sorry ih8bills,

But could you explain to me what does "Rated FSB - is it the maximum speed the FSB is able to achieve?" this point means?