Dual Channel DDR question

[ElementalDragon]

Ok, my nicely upgraded computer should be workin tomorrow since one of the 3 parts i bought were bad. I just have a question about the Dual Channel DDR that is supported by the chipset for the mobo. I have 2 sticks of PC3200 DDR 256MB. Does that mean that if i use them for Dual Channel, that it would act as if the 2 sticks were (in theory) one PC6400 800Mhz 512MB stick of DDR?

 

[Heeter]

No E,

It means that 2 x 400mghz DDR (DualDataRate) pipelines(channels) will be enabled from the cpu.

Heeter

 

[ming]

Yup, dual channel of double data rate (DDR) memory for you.
Acts like a highway with two lanes of traffic instead of just the single one.

 

[LeeJend]

Mostly yes. I think there is an FSB bandwidth bottle neck that keeps them from getting all the way to "6400".

 

[ElementalDragon]

well... that's kinda the way the dude at the comp show phrased it. having 2 sticks of PC3200, it would practically be running at 800MHz instead of 400MHz, which is kinda the same thing u just said. it's 2 sticks of ram running on separate channels, which means it can transfer data 2 times faster. i dunno. makes sense in my head. If you look at the pdf file in the attachment, it even shows u all the benchmark differences and stuff between running PC3200 DDR on Single Channel, and on Dual Channel. and at the one part, for Single Channel it shows the peak memory bandwidth is 3,200KB/s (being the 3200 part), and for Dual Channel, it shows the peak memory bandwidth as 6,400KB/s (following above rule, would be PC6400). either way... it's a drastic increase in speed over Single Channel DDR, or in my case, a single stick of what i guess would be PC133 SDRAM

 

[Goatman]

actually, usually the way it ends up working out on nForce 2 motherboards, is it gives one channel to the Video, and the other to the CPU.

 

[dreamliner77]

only if you have on board video

 

[ElementalDragon]

which my mobo does not. GigaByte 8IK1100

 

[Sazar]

the only time you are really noticing dual channel is likely to be with the FX lineup from amd or the intel p4 canterwood lineup...

they have the best implementation with noticeable difference in bandwidth limited situations...

you just have more AVAILABLE bandwidth... your fsb is not changed in anyway.. ergo yes... throughput is better

now... all the bandwidth gains are EXPECTED.. they are not the actual gains therefore you are unlikely to see them other than in synthetic situations for the most part or highly memory intensive situations as some professional software and office software calls for...

 

[hylowa]

technically... 200mhz(ddr400) in two channels, works at an eefective 800mhz(2 x 200x2 = 800 theoretical) also, your sending 128bit blocks of data, rather then 64 bit chunks as with single channel...
assuming your using a 800mhz bused p4, you would get a very efficant system bus... the same if your usin a 64 fx

i think we all said exactly the same thing like 10 times, but, i wanted to say it to

 

[ElementalDragon]

lol. u kinda had a typo. DDR400 operates at 400mhz, not 200mhz. (hence the 400)
and the processor i'm runnin is a P4 2.4 GHz w/ HT

 

[blinden]

no, DDR400 runs at 200x2

 

[ElementalDragon]

same difference

 

[Shamus MacNoob]

And you do see a big difference in whatever you do when you use the duel channel I have tested mine in single channel and duel channel mode and no matter what you use when you set it to duel channel and match the fsb/ram ratio to 1:1 or 100% it screams speed .... I run faster than a 3200+ in both read and write with my setup

 

[Shamus MacNoob]

no, DDR400 runs at 200x2

And an intel P4 runs at 200Mhz to but go figure they say 800Mhz front bus

thats some wacky math eh

 

[Goatman]

It's 200 X 4

They Quad Pump their bus...

 

[Shamus MacNoob]

Yes I know but that dont mean much just look at the new cpu they are putting out .. its less performing , takes more power I have my doubts about intel seems they are on the wrong track ...

 

[leedogg]

i have a question. I have an Asus A7N8X which supports dual channel. I currently have a 512 stick of pc2700 and 2x256 sticks of pc2400. I'm not sure whats going on if dual channel is being used or what. Any recommendations on how to configure my ram optimally? i.e just use the 2 x 2400 sticks or just the 2700...or would you recommend getting new ram altogether? and what is the optimal Ram rating now? pc3000?

 

[ElementalDragon]

If your mobo can support it, it's up to 3200. you could buy 2 new sticks of 256MB of whatever DDR your mobo supports to get the best out of the RAM. If not, then i'd say use the 2 sticks of 256

 

[Shamus MacNoob]

if you set the ram to a speed = the the lower stick and run it #1 and #3 the same and the odd one out in #2 it should work in dual channel at the speed of the lower sticks , I have 2 dual channel MOBO's one MSI and one GIGABYTE both use 3 stick of ram in dual channel mode , MSI = #1=128mb #2=256mb #3=128 for a total = 512mb in dual
GIGABYTE is #1=256mb #2=512mb #=256 total = 1Gig Dual channel



Too see if the dual channel is enabled there are a few programs that can read that info cpuz , and also the Nvidia utilities

here I attached cpuz