But the FSB is the data bus between the Memory Controller Hub [Intels name], which is part of what is generally known as the Northbridge chip of a chipset, and the CPU.
The speed of this bus gets multiplied by the CPU's internal multiplier to set the internal CPU speed.
The 64 bit AMD CPU's has located the MCH on the CPU die, so the FSB for them is inside the CPU.
The remaining functions of the Northbridge stay in the chipset.
Exactly what does the FSB do? Is it the data bus? Where is it on the motherboard?

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