optimizing performance between cpu and ram

[NanoWarrior]

How do I optimize performance between the processor and the ram? I suppose it would have to do with the FSB rate but how would I go about matching the processor and ram FSB to get best performance?

Also what is duel channel? They say its doubles bandwidth but what bandwidth...the FSB rate?

 

[Apokalipse]

you basically want to synchronize the processor's FSB and RAM data transfer speed, or make sure the RAM is running at a multiple of the processor's FSB - the RAM itself operates internally at half the speed
the RAM data transfer speeds are as follows:
PC2100: 266MHZ or 133MHZ internal
PC2700: 333MHZ or 166MHZ internal
PC3200: 400MHZ or 200MHZ internal
PC3500: 433MHZ or 216MHZ internal

if your processor has a FSB of 333MHZ, then PC2700 RAM is the one to get, if it has a FSB of 400MHZ then PC3200 is the one to get
if your processor has a FSB of 800MHZ, you'd get PC3200 because 2x400=800MHZ

 

[NanoWarrior]

if your processor has a FSB of 800MHZ, you'd get PC3200 because 2x400=800MHZ

They will double up like that,COOL, but Isn't duel channel suppose to do that?

 

[Apokalipse]

yes I think so, it can work either way
2x400MHZ sticks that make 800MHZ, or 1 400MHZ stick that makes a multiple of 800MHZ

 

[NanoWarrior]

what your tellin me also compatible for the amd 64 bit athlon processors right?

also...So I suppose duel channel active ram would double fsb rates, like 2 sticks of 400mhz would jump together to 800mhz?

 

[wansingct]

2 sitcks of 400mhz do not equal 800 mhz. This used to be how rambus would run their numbers and they were full of it. with a configuration like that, you get 800mb/s of effective bandwidth, but your ram is still running at 400mhz. Think of it like a river. If your river is wider (mb/s of bandwidth) it doesn't have to flow as fast (mhz=speed) to carry the same amount of information. The bottleneck usually comes in when you do not have enough memory bandwidth between your processor and your memory controller. Improving one usually hides the deficiency of the other, but they are not the same.

Dual channel ram is to the memory bus like dimms are to simms. Dual channel ram just means that the information meant for two separate sticks is not competing for the same pipe.

The ideal world is to go with how the athlon 64's do it and have the memory controller integrated directly into the processor. That way, there is less latency as the processor does not have to "look up" where the info. its looking for is in the ram. the integrated hypertransport inks in the 64 bit cpu's from athlon is one of the best things they've ever done.

 

[NanoWarrior]

Then how would you ever get the ram FSB speed to match up with the athlon's 64 bit processor's FSB speed when the processors intergrated into chip speed is 800 mhz? There is no ram that fast.

Also if duel channel active ram does not share the same pipe? then I suppose It has 1 for each but what would it help with?