[clug] OT: DDR RAM and FSB speed

Darren Freeman daz111 at rsphysse.anu.edu.au
Wed Jan 26 22:09:41 GMT 2005

On Mon, 2005-01-24 at 13:57, Steve Walsh wrote:
> He's Close, but he's also very very wrong.
> DDR400 is hit twice in a clock cycle, so whilst it is hit only at 200Mhz,
> due to the fact it loads twice per clock cycle it is effectively running at
> 400Mhz. He's been caught by the SDR/DDR conversion.(DDR266 runs at 133, DDR
> 400 runs at 200, but 200Mhz is a lower number than 266, so therefore it all
> works out in his head) Thankfully, the board in question should auto detect
> that it has slower ram and run accordingly.

I think you missed the question and I think he knows the SDR/DDR

Brett asked for PC3200 RAM and got quoted PC2100 RAM. He wants to know
if the motherboard will interleave two sticks of RAM to make up for the
fact that one stick is slower than the FSB. I don't think he wants his
shiny new Dual Xeon to detect the slower memory and run slower.

Have fun,

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