Questioning about FSB

[Maranho]

I found that the concept of FSB no longer applies, so I would like to know what 
replaced this feature and how to proceed with the calculation of the external 
frequency ratio multiplied by the multiplier factor to obtain the internal 
frequency of the processor?
Thank you for your attention

[n_scott_pearson]

The FSB connected the processor to the MCH/GMCH portion of the chipset. With these portions now being integrated into the processor itself, there is no longer a FSB, per se, in the architecture (as least as an external entity). In Intel processors, the DMI bus connects the processor to the PCH, which subsumed the functionality of the ICH.

The concept of an external clock and a clock multiplier still exist today, but you really cannot make this type of (global) calculation any longer. Today, various features allow the clock multiplier to be varied, on a core-by-core basis, and, in specific situations, to even exceed the base clock multiplier. For more information, here's a place to start: Technologies Defined for Intel® Mobile and Desktop Processors.

Hope this helps,

...S