basic bus speed settings question

chedderslam1

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Aug 27, 2007
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I am looking at the info displayed by cpuz here. It shows the bus speed @ 133 and the rated fsb @ 533. Does the bus speed of 133 mean that the memory is running at 133? the SPD tab timings table shows that all three memory sticks are capable of 166 and 200 mhz timings. Can I safely increase the fsb speed to 166 or 200 to get the most out of the memory? Would I have to adjust the cpu multiplier down to compensate for the higher bus speed? What does the 533 mean?

Basically, I am trying to learn how to properly set the bus speeds in bios to get the most performance out of the equipment I have.
 

kamkal

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Jun 5, 2007
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the memory speed is determined by some ratio in relation to the actual FSB

so in this case, the actual FSB is 133

if your ratio is 1:1 then yes the mem will run at 133

if your mobo allows, you can go into the bios and change the mem to fsb ratio to get the mem to operate faster

something like 3:2 would give you a mem speed of 200 (133 * (3/2) = 200)
 

kamkal

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intel "quad pumps" their FSB to give you 4x speed of actual speed

so thats where the 533fsb comes into play

if you increase your FSB speed, you in turn will increase your cpu speed and yes if you manually adjust the multiplier down on the CPU you will compensate for that
 

Peaks

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Its good to start with your cpu to memory ratio at 1:1 to make sure you don't bump over the maximum speed of your memory. So your memory shouldn't have a speed greater than 200. Just start with the ram divider at 1:1, do some calculations and go from there.

What CPU and Motherboard do you have?