Expected Frequency	This is the frequency at which Intel intended the processor and the system bus to run. This should be the speed physically marked on the processor's packaging.
Reported Frequency	This is the actual operating frequency of the processor and system bus as measured by the utility.
Overclocked	Processors or system bus that run above their expected frequencies are considered to be overclocked. Overclocked processors or system bus can produce unpredictable results or system instabilities, which might not be readily apparent. The life of the processor may also be shortened.

This applies to:

Intel® Pentium® II Processor Intel® Pentium® II Xeon® Processor Intel® Pentium® III Processor Intel® Pentium® III Xeon® Processor Intel® Pentium® Pro Processors Intel® Pentium® Processor Intel® Pentium® Processor with MMX™ Technology Intel® Processor Frequency ID Utility Mobile Intel® Celeron® Processors Mobile Intel® Pentium® II Processors Mobile Intel® Pentium® III Processor Mobile Intel® Pentium® Processors OverDrive® Processors