The system RAM memory prevents the PC of achieving its maximum capable performance. This happens because the processor (CPU) is faster than RAM memory and usually it has to wait for the RAM memory to deliver data. During this wait time the CPU is idle, doing nothing (that's not absolutely true, but it fits in our explanation). In a perfect computer, the RAM memory would be as fast as the CPU.

But it is very unprobable that RAM memory will one day reach CPU speed. Nowadays with processors running over 3 GHz, RAM memory is still stuck at 400 MHz (actually less than that as we will explain below).

Many years ago one idea was created to match CPU speed with memory speed, which is used until today. The processor has two speeds, one internal – which is the one labeled on the CPU, like 3 GHz, 3.2 GHz and so on – and one external, used to access the CPU's outside world, specially RAM.

But even with this technique the speeds don't match. Intel CPUs available today run externally at 400 MHz, 533 MHz, 800 MHz or even 1,066 MHz, while the RAM speed is still stuck at 400 MHz, at best (there are 533 MHz DDR2 memories emerging on the market but they are still rare).

Dual Channel Memory can help improve the RAM speed, because this technique doubles it. In order to use Dual Channel Memory, your motherboard has to be capable of supporting this technique and you will also need two equal memory modules. We'll explain this further, but first let's understand deeper the bottleneck problem.