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Hi,

I am planning to upgrade my machine's memory from 1G (512+512) to 2G. My mobo is Intel 946GZ(IS).
Well it has only 2 DIMM slots. As both of my slots are occupied; I had to ask the local vendor to buy back the two 512M RAMs and instead give me 2 1G RAMs at whatever extra cost.

His claim is that even if I put in one module in one DIMM slot; that'd work as dual channel memory.
I could not prove/disprove my view of having two modules; nor his.

Is there a way I can?

The manual has a topic on that, read it . As for me, both my Asus and Foxconn mobo's need an even amount of chips to enable dual channel memory.

"Dual-Channel" is a term describing the data thouroughput (2 64-bit channels at each end instead of 1). You can still just use one memory module in a ddr2 setup and be fine, you dont need to have two modules for them to work.

I have a NForce 780i and I know it requires you to use an even number of modules for Dual Channel. Using 1 or 3 will end up knocking you back down to 64 bits. Combuster is right though, your motherboard manual is the best place to find out memory configurations it can use.

Almost every DDR and DDR2 motherboard in existence needs two sticks to run in dual channel mode.

I meant - is it possible to write a program that can tell if it is operating on dual channel memory?

(Sure the manual says you need two equal sized modules plugged in two DIMMs; but there are people, specially where I live, who do not believe in mapping between documentation and actual hardware. There have been fraud-cases. )

Hi,

Have a look at the memory selector tool at -> Crucial <-. In addition to telling you what memory they want to flog you, running the tool also offers some quite useful FAQ's about your memory controller, such as information about dual channel, buffered and unbuffered DIMM's and so on...

Cheers,
Adam

CPU-Z can tell you if your mobo is operating in dual channel mode (I think)....
Dual channel requiers that the same amount of memory in the same config (e.g. same amount in each slot) is installed on the two channels and they ave to have the same speed and CAS latencies.
There are also certain issues with parts from different vendors working together due to slight differences in hoz they use the normal communication protocol...
Jules

[quote="prashant"]Hi,
His claim is that even if I put in one module in one DIMM slot; that'd work as dual channel memory.
quote]

That's incorrect.
You MUST have an even amount of memory modules with identical vendor/models in order to utilize the dual-channel technology. Even if you have both slots filled but with a stick of different memory in each, dual-channel will not kick in and your memory speed will drop down to the same speed as the slowest module installed.

01000101 wrote:

prashant wrote:Hi,
His claim is that even if I put in one module in one DIMM slot; that'd work as dual channel memory.
quote]

That's incorrect.
You MUST have an even amount of memory modules with identical vendor/models in order to utilize the dual-channel technology. Even if you have both slots filled but with a stick of different memory in each, dual-channel will not kick in and your memory speed will drop down to the same speed as the slowest module installed.

Why did you have to repeat that?
Jules

Obviously, he made a error...

inflater wrote:Obviously, he made a error...

What I meant, was why did he have to repeat what I said?
Jules