Memory not going actual speed its supposed to.

[will h4x 4 food]

I have a DFI ultra-d and a 3700 SD and i overclocked it to 2.64(240*11) with stock cooling. i used a 5/6 divider on the OCZ performance RAM and on a calculator the speed should be 200 mhz exactly, but on cpu-z and everest it shows up as 188 mhz. why is this???

 

[HAVOC]

PM - gaara or nubius

They will best answer your question.

 

[Mach1threat]

i had same problem but mine would only come up at 166 mhz... Its corsair ...that may be the problem

 

[Nubius]

the memory is not the problem. It's the way the AMD64s work.

I replied to the PM from the owner. Google up a program called:

A64MemFreq11.exe

You put in your HTT, your Multiplier and what memory divider you're using and it'll show you what your memory speed will actually be.

You can't simply find out 5/6 of 240 and expect your RAM to run at that. The formula for figuring out your memory frequency is:

How to calculate your memory frequency

Memory Frequency = (FSB x (CPU ratio)) / ] ((CPU ratio) x (FSB : DRAM ratio)) [

Ceiling function is shown with ][,
eg
]10.1[ = 11
]10.2[ = 11
]-6.2[ = -6
]-8.9[ = -8

For positive numbers always round up to the nearest whole number.
For negative numbers always round down (its actually still up) to the nearest whole number.

Big example
FSB = 290
CPU ratio = 7
DRAM:FSB ratio = 5:6, re-arrange to 6:5 (FSB : DRAM)

Using the formula,
Memory Frequency = (FSB x (CPU ratio)) / ] ((CPU rato) x (FSB : DRAM ratio)) [

Memory Frequency = (290 x (7)) / ] ((7) x (6/5)) [

Work this bit out first
] ((7) x (6/5)) [

6/5 = 1.2

and that becomes
] (7) x (1.2) [

7 x 1.2 = 8.4

Now remember the ceiling function, ][

]8.4[ = 9

Put that back into the main formula

Memory Frequency = (290 x (7)) / 9

So
Memory Frequency = (290 x 7) / 9
= 225.5Mhz.

 

[will h4x 4 food]

ooo ok, thanks for your help u guys.