400 MHz nForce2? I think not!

[superdrunk]

Hello all,

Long time reader, first time poster. I'll cut to the chase though. I recently upgraded my motherboard and memory for my PC. I was running an ASUS A7V333 with PC 2700 RAM and an Athlon XP 2000+. Things were happy, until an unfortunate dust incident caused it to overheat and crap out (how's that for technical jargon?).

So, I called in the warrenty, but I also took the oppurtunity to convince the wife that I needed new components, so I went with an ASUS A7N8X, and I also invested in some Corsair PC3200 TwinX modules. Everything arrived on time yesterday, and I set to work.

I plugged in my "new" processor and I made sure I plugged in my ram to take advantage of the TwinBank architecture, and when I booted up, it detected that my processor was an "AMD Athlon 1250 Mhz." I did a little digging, and the motherboard was detecting my processor bus was at 100Mhz, with a clock multiplier at 12.5x. So after upping that to 133Mhz, I get my correct speed. Problem solved? Not really. My main question is: The board is telling me that my memory is running at 200Mhz (right on the POST screen). How do you achieve 400Mhz? Is it possible? How should I set my multiplier/external clock? Is it set right? If I try to change the RAM settings in the BIOS, upon a restart, I get a blank screen, no BIOS, no post, no beeps. Then I'm forced to short a jumper to reset my defauts (which I got sick of, and that's why I am here).

Am I about to toast another AMD product? Can anyone help me?

Thanks for everything in advance.

-superdrunk

 

[AlphaFox]

400Mhz is marketing. its 200Mhz DDR, = 400Mhz. but, since your cpu bus is only 133mhz only the ram is running at 200 (400ddr) and this is actually slower. the best thing to do is set it syncronously, so 133 for both. the ideal situation is to set the fsb of the cpu to as high to 200 as you can and set the ram to the same speed, if your cpu allows it. (unlocked, but with nforce2 you dont need to unlock it, at least I didnt) I have my cpu and ram set syncronously and the fsb is set to 180 so both the ram and cpu run at 180 which is like 360Mhz ddr. its the best I can do.

 

[superdrunk]

So what you are saying is: Even though when I boot up and it says "Memory Speed is 200Mhz" the board is running PC 3200 at the capacity? So there isn't much I can do?

 

[vk2amv]

Everything is working as it should be. The 400Mhz is a myth. Same as intel 800Mhz FSB is also a myth. It is just marketing nothing more. 400 is 200Mhz Double data rate and 800 is 200Mhz double data rate in dual channel making quad data rate. Neither truly do 400 or 800Mhz speeds. It sounds as if you have everything set fine. Just leave it as i is. The FSB of the CPU would be running at 133Mhz and the memory at 200Mhz and even though it is async the lower latency of the memory gives a boost.
AREA_51

'It's only when you look at an ant through a magnifying glass on a sunny day that you realise how often they burst into flames'

 

[lwj81]

You need to set the cpu/fsb-mem/freq divider to the same ratio (3/3,4/4 etc.).With the fsb at 133 it should post the memory at 266.To run the memory at 3200(400mhz),You will need to up the fsb to 200 with the same ratio divider.

 

[Crashman]

So there isn't much I can do?

There isn't anything TO do! Your CPU for example runs on a 133MHz bus, which AMD named 266MHz because it has double data rate, aka twice as many transfers per cycle. The same goes for Double Data Rate memory, 200MHz translates to DDR400, which is 3200MB/s, hence the name PC3200.

You can do the math, 200x2=400! And the memory bus is 64-bits wide, since 8 bits= 1 byte, divide 64/8 to get 8, and 8x400=3200.

<font color=blue>Watts mean squat if you don't have quality!</font color=blue>

 

[error_911]

thats why its called "DDR" RAM, because its Double Data Rate RAM, therefore your "200Mhz" RAM setting on the mobo is actually 400Mhz once it has been multiplyed-out by the mobo, so no worries, its all workin' right

<b>I'm
just
taking
up
space.







Heheheh, and you thought I was done</b>