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General discussion

(NT) What does FSB stand for and what to look for in a cpu?

Aug 9, 2004 3:52PM PDT

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Re: (NT) What does FSB stand for and what to look for in a c
Aug 10, 2004 12:11AM PDT

front side bus - cost, performance, reliability, cost, matches your motherboard, cost, your desired applications, cost

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FSB is Front Side Bus as in prior answer.
Aug 10, 2004 7:53AM PDT

It is the speed of the bus between the Northbridge or Memory Controller Hub [MCH] [Intels name]and the CPU.

The FSB capability of the CPU is only acheived if you are using the correct memory type and running at the correct memory bus speed on the mobo. At the rated FSB the multiplier built into the CPU multiplies the FSB up to cause the CPU to run at its core frequency in GHz. [example: if the FSB is 200 and the Multiplier 11 the CPU runs at 2200 MHz.]

EXAMPLE: A 333 FSB is acheived using 166MHz DDR memory [also known as PC 3200]. 400 MHz FSB requires DDR 400 [PC 3500} 200 MHz DDR.

DDR memory makes reads or writes twice per cycle, that's why the numbers get multiplied by two.

If you don't have the correct speed memory the FSB will run at a slower speed and the CPU will run at its multiplier times that lower speed. Doesn't hurt the CPU. Perfectly OK if one doesn't have the faster memory.