computer processor oscillator section

[electonicsproject]

hello
when i open my computer i does not see any crystal oscillator with amd processor but screen setting show 2.81ghz where as ram also has the frequency in ghz but different
please clear doubt.

 

[FvM]

If I take an arbitrary processor board and look sharp, I see one or several SMD or metal can crystals and possibly a dedicated clock synthesizer chip. With newer chipsets, the clock synthesizer function may be included in a processor support chip.

Review handbooks and reference designs of PC processors and their support chip sets to learn about details.

 

[electonicsproject]

how 2.81ghz is generated is it similar to square wave?
the ram has also freq
but when i used 8085 it work with one crystal oscillator 4mhz
i have used paralax quick start board it has PLL which make 80mhz how does pll work?