RAM: Single, dual, triple channel, flex mode, interleveled.

You probably heard about these memory set ups before, but you don't exactly know what to do about it.

For our practical example here, we will use a motherboard that supports dual channel (this applys for triple channel as well)

You will probably wonder what is the differance between single, dual and triple channel.


Well, there is a data bus between the memory chips and the CPU.
Each channel has 1 buss, that goes to the CPU.
Now, if we have a single channel configuration, only 32 (or 64 depending on CPU) bytes of data will go to the CPU at any given time

In dual channel, you virtually double the amount of data transferred to the CPU at any given time, thus making your PC faster. It is NOT twice as fast, it is just "faster". This happens because there are now 2 buses through which data goes to the CPU

Same apply s for triple channel. It has 3 times the data flow of single channel.

Although you may not notice any difference at first, your computer will run faster when using multi channel configurations.

So those are your memory slots
The red channel is channel A, the black channel is Channel B.

Now, we have several memory chips available, and we will play around with em.
Case #1 Dual channel

Lets say we have 2 (or 4) identical memory chips.
That means they have same voltage, frequency, density and timings.
And we want to put those in dual channel.

If we have 2, we can only out them in slots of the same color.
On some mother boards, puting 1 in black and 1 in red will enable them to work in single channel.
on others, the computer will simply stop working.

If we have 4 identical chips, we put 2 in black and 2 in red. And we run in dual channel.

Case #2. Dual channel inter leveled
We have different chips. but same dimm (aka DDR2, or DDR3. You can't mix different DDR)
But they have same density (aka all of them have 2 GB for example)

This type of dual channel is called "inter-leveled"
so we have chips A: with 2GB density, 800 Mhz, 5-5-5-18
and we have chips B with 2 GB density, 1066 Mhz, 5-5-5-15

To get dual channel, we put type A of chips in either channel A or B (aka the 2 identical chips must stay in same color slots) and B type in the other slot.
that means chips B will noow run at 800 Mhz, and 5-5-5-18 timings.

the higher specification chips, aka the B chips, will run at lower specifications.
they will have same frequency and timings as the A type.

Case #3 Flex mode

We have chips with different density.
although not recommended, as some mother boards won't take this very friendly, you can force these chips to run in flex mode.
If you put chips with different density in same color slots, they will run in flex mode. This means that some areas of the higher density chip will be running in dual channel, while others in single channel.

 Case #4 Single channel

this is obtained in 2 situations
1) you only have 1 memory chip installed
2) you have more chips installed but placed in different colored slots.


For triple channel, you simply need 3 or 6 chips instead of 2 and 4.