Internal Clock, External Clock, Clock Multiplier of Microprocessors Confusion

This is what I know. Clock signal is generated by an IC on motherboard. It has a reference crystal clock, and based on that it generates a faster clock signal. Is it the internal clock of the microprocessor? And where is this crystal located? on processor or motherboard?
The internal clock for microprocessor is obatained as a multiply of the external clock, and the you call it multiplier, where is this external clock come from? Is it the clock signal? Various motherboards have various FSBs. And some CPU has only one multiplier that cannot be changed? Then the cpu must run at different at clock speeds in different motherboards. This is my confusion. Can someone help. I searched every term I know but I'm stucked. Can you give some reference?

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I read them, so this means that motherboard senses the microprocessor and sets a clock signal based on manufacturers recommendation, and it is the external clock for the cpu. The internal clock of the cpu is obtained by the external clock multiplied by the multiplier, and the multiplier is a constant. So i guess the crystal for the clock generator is in the motherboard. Thanks

The reference clock is usually quartz and n the motherboard somewhere. There will be a PLL IC nearby which multiplies it to produce the various signals used around the board. One of these will go to the processor which has it's own internal PLL to further increase the speed it runs. It wouldn't be feasible to run a fast clock along a PCB track to the main processor, at such fast speeds it would require microwave transmission lines to carry the signal and matching impedances through multi-layer boards, plugs and sockets would be almost impossible.

Brian.

Crystals are like 30 year old technology. Today, the clock frequency for the motherboard comes from an oscillator.

Anyway, if you are looking to change the settings, you need to get into your BIOS. Doing that is not exactly straightforward as every manufacturer does it differently. Generally, there is a key that you press during the POST. Could be <esc> or any of the F-keys. Even then, if you have a graphical screen during post, you have to disable that so that you see the text during post to get to that point, which again is one of the above keys. Watch your boot screen carefully when you power on and you should get the specific instruction (but it will not be on screen for very long).

Then you need to know your way around the BIOS. If you can get the specific model of your motherboard, you can DL a manual from the manufacturer. Actually, that should also tell you how to get into the BIOS in the first place so do that before anything else.

Keep a notebook handy and write down any settings before making changes or you could end up locked out of your computer.

The motherboard frequency is generally called FSB or Front Side Bus. The CPU multiplier is what it is.

I find it helps to have a second computer nearby running a spread sheet. I put the allowable FSB settings in rows and the CPU multiplier setting in the odd numbered columns, with the even numbered columns for any notes that I want to make.

Also, set your FSB to about half what it defaults to when you are playing with multipliers and your multiplier to half way when changing the FSB.

If you want to get into hard core overclocking, there is a good deal more to this to deal with but that is enough to probe your basic settings.