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Is the overclocking guide correct?

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Originally posted by: BTRY B 529th FA BN
As far as I know and correct me if I am wrong:

bus = 133, 266, 333, 400 and its given that they can be manipulated lower or higher giving different results to total CPU speed for locked multipliers.
With DDR, the MEMORY bus is always doubled cause its double the data rate. What ever memory you buy be it DDR, DDR2, DDR3, etc. the number (i usually use "number" e.g. DDR(X) [number]) is the final number the (bus speed x 2) is divided into, hence the ratio.

Is this wrong?

EDIT: I added the word "MEMORY" to your post above, to make a distinction between the Front Side Bus (FSB), and the Memory Bus

I don't know if I fully understand your question, but I will try to elaborate on what I have said earlier.

The "3" in DDR3 means "Double Data Rate" 3-rd generation. It has nothing to do with the ratios - it is still the Double Data Rate, which means x 2.

But before you double the frequency, you have to get the Memory Bus running at the specific frequency, and that happens by the use of Memory Multipliers, known as the FSB:RAM ratios.

Example:

400MHz FSB x 2 Memory Multiplier (for the 2:1 ratio) = 800MHz Memory Bus frequency

Now the DDR comes into play, doubling the 800MHz to 1600MHz for the final Memory Frequency.

Another example:

500MHz FSB x 8/5 Memory Multiplier (8:5 ratio) = 800MHz Memory Bus frequency.

DDR will double this to 1600MHz, for the final Memory Frequency of 1600.

Hence, the 400MHz is not the maximum FSB for the DDR3 1600, because the 500MHz FSB will work, too.


Just like I said before, everything revolves around the "basic" FSB speed.

That "basic" frequency is then:

- "Quad pumped" for Intel CPU's for the "final" FSB speed (like ex. 4x500 = 2000 MHz)

- "Multiplied" for the "final" CPU frequency (like ex. 8x500 = 4,000MHz)

- "multiplied" with the use of "Memory Multipler" (which can be a fraction, like 2:1 or 8:5), for the "Memory Bus Frequency", which ONLY THEN is doubled as DDR (like 8:5x500 = 800MHz Memory Bus Frequency x 2 Double Data Rate = 1600MHz).

Hope this helps.
 
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