One more Dual DDR question.....

Dual DDR is being used for the P4 as the bandwidth of a 533MHz FSB P4 is not met by a single DDR channel, but would be met by a dual DDR channel controller as there is twice the bandwidth from it.

My question is, could you run an Athlon at a very high FSB, run the memory slower, but use dual Channel DDR mobo, such that the Bandwidth needs of the CPU are still met by the bandwidth from the two channels of DDR?
E.g.:
CPU bandwidth:
(64/8)*400FSB = 3200
Memory bandwidth:
(64/8)*266FSB*2channels = 4250

So by using dual PC2100 DDR (cheap enough), you can still provide enough bandwidth for the 400MHz FSB of the CPU, with almost a 1/4 of the memory bandwidth to spare.

Is this theory correct, or am I missing a bit which makes it all do-do?

I think it would work, but I could be wrong

one must try one day

Yes you can, unfortunately, dual channel for AMD does not yet have high efficiency. I've seen benchmarks. Two sticks of pc2100 in dual channel cannot match a single stick of pc2700.
Running dual channel at 4/5 fsb and setting the FSB to 200 will get you only about 3200mb/s bandwidth. This is about the theoretical max of the CPU, but it's only 100-200mb/s more than a single pc3200 stick.
In other words, if you have modern equipment, it's not worth upgrading.

strokeside, nice avatar!

decepticon! baught my son some transformers for x-mas last year.

i remember the days when optimasprime was the s%$t. i think it was back in "81". ya those were the days. no worries.

back to the subject.

caffinehog is correct. the dual channel thing hasn't got its act together yet. i would hold off till the next generation of dual channel boards come out. unless you are planing to buy a barton when they come out at the first of next year. but i would still wait.just my oppion!

I am switching from intel to AMD platforms and was trying to find ways to make the price of my new system as low as possible, but still have a great system. I think I will just go with one good stick of RAM, and buy another one later down the road if the next gen of dual ddr boards give good results, (but by then it might be DDRII so ...............a hell), I'll just wait and see.
thanks.

DualDDR for Athlons = waste. Unless you're using onboard graphics, then it's great.

Magic words for Athlon systems = Corsair XMS.

Ok, say you got your Athlon up to 200fsb. That's effective 400mhz. Don't bother running more than 400Mhz of effective memory bandwidth. It's a waste. A stick of Corsair XMS PC3500 is your best friend. It'll take any fsb you throw at it on an Athlon up to 217mhz, and since you shouldn't run your memory any faster than the bus, you might as well put some aggressive timings on it, which it is also rated to do.

Basically, a single stick of really nice DDR (like the Corsair XMS) will meet the bandwidth needs of any Athlon system out there. Unless, of course, you have one absolutely insane overclocker.

Stumpjumper5200 said:

DualDDR for Athlons = waste. Unless you're using onboard graphics, then it's great.

Click to expand...

Actually, dual DDR could become awesome. Remember, Nforce 2 is just the first generation of this. When dual DDR gets something like a 50% performance increase over single, and sticks can be run at 2/3 of the FSB, then this will let you get you pc3200 bandwidth with pc2100 running at stock speed. Definately a huge incentive to buy that generation of board. For now, however, it is a waste.

so what mobo do you guys recomend? isnt the nforce the best performing mobo out right now? and if not then what is? cause the nforce and the kt400 are around the same price. so which should i get?

Get something like the A7N8X. It has a locked PCI bus, and therefore overclocks the best, dual ddr aside.