Confused about calculatin dividers with A64, is this how its done?

[Guest shaolin95]

QUOTE FROM AMDMB "I was calculating improperly however, prior to your post.

 

I thought a 166 mem setting would be 166/200= .83 taking the frequency (let's say 275) 275 x .83 >>>> giving a RAM speed of >>> 228.25.(Wrong!)

However if I have this right the divider is determined by the STOCK frequency of a given processor, as you pointed out. The RAM divider is: 2200/166=13.25

 

So if I have this correct an A64 3200 is 2200 stock and using a 166 memory divider with a overclock of: 10 x 275 = 2750 the RAM runs at 2750/13.25 or 207.50.

 

I think the lesson here is that memory dividers are applied to the CPU stock speeds to provide the correct RAM divider.

 

Now do I have this right? If not let's fix it. (set me straight if need be)" END QUOTE

 

I am totaly confused now as I was using the first method mention and even a program called A64 MEM FREQ 1.1 calculates it like I do. Which is the correct way?

 

Lets do an example here:

@183MHZ memory

My CPU 2400/183 = 13.11

my CPU 8x313 = 2504MHZ/13.11 = 190.99MHZ...is this my real mem speed?

 

 

 

Regards

[THunDA]

Check out THIS guide out.. and there is a program that does it all for you too..

[Guest shaolin95]

Thas was the way I was doing it but this post really confused me, read the last page,

http://forums.pcper.com/showthread.php?p=3355385#post3355385

[psy^]

CPU half multi are just wack, don't use them.

RAM dividers work off your current HTT (FSB) speed, not the stock one. I don't understand where that idea came from, it makes no sense.

 

E.G: If i run a 300HTT and set the ram to a 5:6 divider and run Memtest86+, i can clearly see the RAM is running @ 250Mhz, which is equal to (300/6)*5.

 

Let me simplify that ever further ..

 

Dividers like 3:4, 5:6 etc, it's the RAM:HTT divider.

So take the HTT, divide it by the last number of the divider, then multiply that value by the first one. This is how ratios work my friend

[Angry_Games]

not sure if you have seen this table yet provided by Oskar Wu:

 

http://www.dfi-street.com/forum/showpost.p...978&postcount=3

[THunDA]

CPU half multi are just wack, don't use them.

RAM dividers work off your current HTT (FSB) speed, not the stock one. I don't understand where that idea came from, it makes no sense.

 

E.G: If i run a 300HTT and set the ram to a 5:6 divider and run Memtest86+, i can clearly see the RAM is running @ 250Mhz, which is equal to (300/6)*5.

 

Let me simplify that ever further ..

 

Dividers like 3:4, 5:6 etc, it's the RAM:HTT divider.

So take the HTT, divide it by the last number of the divider, then multiply that value by the first one. This is how ratios work my friend

 

 

Now that makes sense..

 

good explaination.. alot of the guides out even confused me..

[odeboo]

I've read the dicussions about using dividers and understand the math. What I don't understand is the effect on performance when using them. I gain clock speed while memory bandwidth decreases. Is that good or bad and can I see the difference?

[THunDA]

I've read the dicussions about using dividers and understand the math. What I don't understand is the effect on performance when using them. I gain clock speed while memory bandwidth decreases. Is that good or bad and can I see the difference?

 

 

There is really two instances where you wana use a divider..

 

One would be if your ram cannot run fast enough to keep up with your htt when running 1:1... so putting the ram on the divider will help you reach your desired mhz without running the ram past its stable point..

 

Two would be when your testing to find your max cpu speed and you dont want the ram to be a variable.. by putting the ram on a ratio and upping the htt and testing with prime or the like you can find the cpu's max without the ram being a problem..

 

Running 1:1 is still the best and most optimal configuration if your ram can keep up with the htt...

 

edit..

 

spelling

[Guest shaolin95]

So I was doing it right all along, cool. I knew that the whole divider based on stock speed was sort of weird :-)

Regards