E-clock on motherboard.....

[CP]

I found that there are two clock-generators on our motherboard. What do they do? How do they related to FSB, AGP and PCI bus frequency?

I have taken embedded system course and the e-clock of the 68HC11 controller is 1/4 of the crytal clock (8Mhz). Are the clock-generators on our PC motherboard equivalent to the crytal clock on 68HC11? What is the e-clock of our motherboard then?

Thanks