Not a Hardware Engineer...not even an Engineer, but do have a smattering of electrical experience. Some links for your review: http://www.devx.com/go-parallel/Article/27399 http://industrial-computers.globalspec.com/LearnMore/Industrial_Computers_Embedded_Computer_Components/Industrial_Computing/Core_Modules http://en.wikipedia.org/wiki/Central_processing_unit As a side note, google "block diagram microprocessor core", and you'll see countless IEEE articles alluding to details of the clocking speeds described WITHIN the microprocessor core. IMO, the processor "core" contains the clocking structure needed to run the processor. Simply, without the embedded clocking structure contained within in the core, the processor cannot be considered in definition, a processor. This does not mean to imply the only place you will find clocking circuitry is within CPU designs. There are all sorts of external clocking circuitry applications used for non-CPU purposes...but for the sake of answering your question, yes...I BELIEVE CPU clocking is embedded in the core/silicon and is necessary for a CPU to function. JMHO, FWIW Regards