I'm Not Sure, BUT!!!

[m411b]

Either the DFI 590SLI board sucks or the OCZ Platinum Rev.2 DDR2-6400 sucks?

[ozzimark]

care to elaborate? :D

i know the dfi is quite picky, but i'm not gonna jump to conclusions :toast:

[m411b]

LOL, I'm tryin to get this piece of SH*T to do what I want it to, but no matter how I try, it just won't do it!

My prob. - I want to make my Proccy to run at rated speed and I want my RAM to run at rated speed.
BUT, I CAN'T.
Either I have to OC my RAM or my CPU.
So, I decided to run my CPU @ 3Ghz stable 24/7, reguardless.
Right now I am running 1 x BIX II, 1 x BIP II, DD TDX, Aquaxtreme Z50, & 7 x SilverStone 110cfm 120mm Fans.

WTF, I can't do it stable.
I AM ABOUT TO THROUGH THIS PIECE OF SH*T IN THE DUMPSTER!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!

[m411b]

MuHahahahahahaha

This SH*T ain't no better then my XP rig!!!!

[Charloz24]

With that kind of attitude, I doubt that you will get some help to resolve your problem.

[ozzimark]

With that kind of attitude, I doubt that you will get some help to resolve your problem.

i agree. i can offer to help you by allowing you to give me your hardware since you hate it so much ;)

if no, then how about actually making sense. you say you want to run both the cpu and memory at stock speeds, but you can't, you have to overclock both. why? why can't you just leave the board at stock settings, that will get both at stock :confused2:

[m411b]

Sry fellas.
I'm just so frustrated over this it's stupid.
CPU= 2.5Ghz
RAM= 400Mhz

If I want to run my CPU @ stock, I have to set my RAM to 357Mhz, which is 43Mhz under stock. Although in BIOS it says 200, which in my mind would = 400Mhz.
If I want to run my RAM @ stock, I have to run my CPU @ 2800Ghz, which is 300Mhz over stock.
CPU Multi= 12.5

So, how do I run them both @ stock?
Without OC?

Do I need to get slower Mhz RAM?
It just doesn't make since.

[doompc]

You can't, since your CPU has a "half multiplier" and the IMC only have integer dividers, @ stock you'll have you RAM doing underclock.
But hey, this is XS who cares about running stock?

[ozzimark]

You can't, since your CPU has a "half multiplier" and the IMC only have integer dividers, @ stock you'll have you RAM doing underclock.

correct, so it's really the cpu's fault even though there is nothing wrong with it :D

just run the cpu at 2.6ghz and be donne with it :D

[mAJORD]

I think he wants to run it at the 3+gig whilst keeping good ram clock.. no?


m411b, do you understand the whole ram divider thing? The ram freq setting in the DFI bios is not actually setting the ram speed at all, just telling the CPU's memory controller what speed rating your ram is (i.e a ddr2-533/667/800 stick) so it can calculate a safe ram clock based on that, And on the assumption of a standard CPU speed..

[ozzimark]

to expand on that post, memory speed is set from the cpu speed:

cpu/x

x = ceiling ( cpu multi / memory ratio )

for the memory ratio..
ddr2-800 = 2/1
ddr2-667 = 5/3
ddr2-533 = 4/3
ddr2-400 = 1/1


so if i set 333mhz htt with 9x cpu multi and ddr2-667....
cpu speed = 333*9 = 3000mhz
memory divider = ceiling( 9 / (5/3) ) = ceiling ( 5.4 ) = 6 therefore cpu/6
memory speed = 3000mhz / 6 = 500mhz

:toast:

[theelectic]

to expand on that post, memory speed is set from the cpu speed:

cpu/x

x = ceiling ( cpu multi / memory ratio )

for the memory ratio..
ddr2-800 = 2/1
ddr2-667 = 5/3
ddr2-533 = 4/3
ddr2-400 = 1/1


so if i set 333mhz htt with 9x cpu multi and ddr2-667....
cpu speed = 333*9 = 3000mhz
memory divider = ceiling( 9 / (5/3) ) = ceiling ( 5.4 ) = 6 therefore cpu/6
memory speed = 3000mhz / 6 = 500mhz

:toast:

Please stop perpetuating this ridiculous "ceiling" stuff, you're confusing the issue even more! Your "ceiling" calculation doesn't even work with all AMD CPUs. What about 8x multipliers considering the lowest memory divider is set at /5???

RAM speed is set by taking the final CPU speed and dividing it by an integer (whole number). For DDR2-400, 533, 667, 800, etc. you want to end up with exactly 200MHz, 266MHz, 333MHz, or 400MHz. Depending on the final STOCK CPU speed, you will NEVER be able to come up with an integer that will get you 200, 266, 333, or 400!

Example: X2 3600+ with 9.5 multiplier. Take the base HTT speed which is 200MHz, multiply it by 9.5 = 1900MHz or 1.9GHz.

To get nearest to 200MHz for DDR2-400, you have to divide by 10. Why not 9? Well, 1900/9 = 211MHz, which is too high. So if you have an X2 3600+ and DDR2-400 RAM, the fastest you can set it at stock speeds is 190MHz, or DDR2-380.

To get nearest to 266MHz for DDR2-533, you have to divide by 8 (237.5), if you /7 you get 271, too high.

To get nearest to 333MHz for DDR2-533, divide by 6 = 317

To get nearest to 400MHz for DDR2-800, divide by 5 = 380

Therefore the dividers for an X2 3600+ are /10, /8, /6, /5.

Keep in mind that the dividers for all AMD CPUs are different. For example, for a 1.6GHz Sempron 2800+, they are /8, /6, /5, /5. Why are the last two the same? Shouldn't it be /4? For whatever reason, the lowest multiplier is /5, so with a Sempron 2800+ or 3000+, the fastest you can run stock DDR2-800 RAM is at DDR2-667 speeds.

When overclocking, the HTT changes, your final CPU speed changes, but the dividers never change. So if you overclock your X2 3600+ to 3000MHz or 3.0GHz, your RAM can run at 300, 375, 500, 600 (double it for DDR2 effective).

See this AM2 divider chart for more info:

http://www.xtremesystems.org/forums/showthread.php?t=105798

[ozzimark]

Please stop perpetuating this ridiculous "ceiling" stuff, you're confusing the issue even more! Your "ceiling" calculation doesn't even work with all AMD CPUs. What about 8x multipliers considering the lowest memory divider is set at /5???
yes it does, i did was forget to include that little piece of information, the equation is valid otherwise. i tend to assume that everyone knows that cpu/4 doesn't exist, but i suppose that might be assuming a bit too much :(
btw, how is it confusing people? is it really THAT hard to divide one number by a ratio and round up to the nearest integer? ;)


RAM speed is set by taking the final CPU speed and dividing it by an integer (whole number). For DDR2-400, 533, 667, 800, etc. you want to end up with exactly 200MHz, 266MHz, 333MHz, or 400MHz. Depending on the final STOCK CPU speed, you will NEVER be able to come up with an integer that will get you 200, 266, 333, or 400!
never eh? what about all the even cpu multis? every single one will give you ddr2-800 just fine :D
but i see what you mean, and i know. it's why the ceiling is there after all, it rounds the calculated number up to the nearest integer so that the memory controller doesn't set the ram speed FASTER than what was desired, as you so eloquently point out later ;)


Example: X2 3600+ with 9.5 multiplier. Take the base HTT speed which is 200MHz, multiply it by 9.5 = 1900MHz or 1.9GHz.

To get nearest to 200MHz for DDR2-400, you have to divide by 10. Why not 9? Well, 1900/9 = 211MHz, which is too high. So if you have an X2 3600+ and DDR2-400 RAM, the fastest you can set it at stock speeds is 190MHz, or DDR2-380.
yup, watch:
ceiling ( 9.5 / (1/1) ) = ceiling(9.5) = 10...
cpu/10
no problems!


To get nearest to 266MHz for DDR2-533, you have to divide by 8 (237.5), if you /7 you get 271, too high.

To get nearest to 333MHz for DDR2-533, divide by 6 = 317

To get nearest to 400MHz for DDR2-800, divide by 5 = 380

Therefore the dividers for an X2 3600+ are /10, /8, /6, /5.
yes, but how do you arrive at those numbers, guess and check? quite inefficient math :p:


Keep in mind that the dividers for all AMD CPUs are different. For example, for a 1.6GHz Sempron 2800+, they are /8, /6, /5, /5. Why are the last two the same? Shouldn't it be /4? For whatever reason, the lowest multiplier is /5, so with a Sempron 2800+ or 3000+, the fastest you can run stock DDR2-800 RAM is at DDR2-667 speeds.
yes and no, the dividers may or may not be different based on what cpu multiplier you are using.. not based on the cpu itself. once you change that cpu multi, the memory dividers change as well, in accordance with the equation i like to dole out so much :D


When overclocking, the HTT changes, your final CPU speed changes, but the dividers never change. So if you overclock your X2 3600+ to 3000MHz or 3.0GHz, your RAM can run at 300, 375, 500, 600 (double it for DDR2 effective).
did i imply that the divider changes with htt speed? :D


anyway, if you're really having trouble figuring out the memory speed, there is a handy calculator for am2's floating around. i'd make one too, but i'm too lazy

[Gautam]

Example: X2 3600+ with 9.5 multiplier. Take the base HTT speed which is 200MHz, multiply it by 9.5 = 1900MHz or 1.9GHz.

To get nearest to 200MHz for DDR2-400, you have to divide by 10.

Oh, gee, I wonder what the mathematical function for taking a non-integer value and bumping it up to the next highest one could be called (http://en.wikipedia.org/wiki/Ceiling_function)? :rolleyes:

There's nothing "ridiculous" about the method ozzimark posted. In fact, if you try plugging in some examples, you'll find its exactly what you just stated, except far more systematic and almost certainly what the IMC is doing internally.


Your "ceiling" calculation doesn't even work with all AMD CPUs. What about 8x multipliers considering the lowest memory divider is set at /5???
And does yours? Last I checked if we take 8x and try and eyeball a speed using your method, we find that CPU/4 is not "too high" for DDR2-800 operation...in either case we have to simply understand that CPU/5 is the lowest.

Really, your method is quite clunky and isn't even applicable for anything besides stock HTT frequency...it was hardly necessary for you to put down the widely accepted and systematic method that ozzimark outlined.

[ILLaViTaR]

Please stop perpetuating this ridiculous "ceiling" stuff, you're confusing the issue even more! Your "ceiling" calculation doesn't even work with all AMD CPUs. What about 8x multipliers considering the lowest memory divider is set at /5???

RAM speed is set by taking the final CPU speed and dividing it by an integer (whole number). For DDR2-400, 533, 667, 800, etc. you want to end up with exactly 200MHz, 266MHz, 333MHz, or 400MHz. Depending on the final STOCK CPU speed, you will NEVER be able to come up with an integer that will get you 200, 266, 333, or 400!

Example: X2 3600+ with 9.5 multiplier. Take the base HTT speed which is 200MHz, multiply it by 9.5 = 1900MHz or 1.9GHz.

To get nearest to 200MHz for DDR2-400, you have to divide by 10. Why not 9? Well, 1900/9 = 211MHz, which is too high. So if you have an X2 3600+ and DDR2-400 RAM, the fastest you can set it at stock speeds is 190MHz, or DDR2-380.

To get nearest to 266MHz for DDR2-533, you have to divide by 8 (237.5), if you /7 you get 271, too high.

To get nearest to 333MHz for DDR2-533, divide by 6 = 317

To get nearest to 400MHz for DDR2-800, divide by 5 = 380

Therefore the dividers for an X2 3600+ are /10, /8, /6, /5.

Keep in mind that the dividers for all AMD CPUs are different. For example, for a 1.6GHz Sempron 2800+, they are /8, /6, /5, /5. Why are the last two the same? Shouldn't it be /4? For whatever reason, the lowest multiplier is /5, so with a Sempron 2800+ or 3000+, the fastest you can run stock DDR2-800 RAM is at DDR2-667 speeds.

When overclocking, the HTT changes, your final CPU speed changes, but the dividers never change. So if you overclock your X2 3600+ to 3000MHz or 3.0GHz, your RAM can run at 300, 375, 500, 600 (double it for DDR2 effective).

See this AM2 divider chart for more info:

http://www.xtremesystems.org/forums/showthread.php?t=105798


wtf? that was perfectly explained, have you even owned a DFI board?

Set the ram to DDR400, it then gives a 1:1 ratio as explained

[m411b]

I think he wants to run it at the 3+gig whilst keeping good ram clock.. no?


m411b, do you understand the whole ram divider thing? The ram freq setting in the DFI bios is not actually setting the ram speed at all, just telling the CPU's memory controller what speed rating your ram is (i.e a ddr2-533/667/800 stick) so it can calculate a safe ram clock based on that, And on the assumption of a standard CPU speed..

mAJORD, you are correct.
My conclusion: I need to stop whinning and being uterly stupid and learn more about dividers!
Which I am going to do all day.