Dual Channel RAM

August 2016

Using dual channel memory equips you with two RAM pipelines to the CPU, to eliminate a bottleneck due to system bus. Most dual channel boards have one stick of RAM set to single mode. To make use of dual channels, you have to get a similar pair of RAM intended for use in your system. If you have 2 sticks of different capacity and memory size, ascertain that they have the same hardware configuration and build. Deploy the RAM in similar colored points, for example, when one RAM is inserted in the blue slot, the other must also be in a blue slot. This will make the dual channel activate. If the colors mismatch, the dual channel mode will not work. Make sure to have the same style chip in both slots of the same color.


Intro


Some memory controllers provide a dual channel for memory. The aim is to use the memory modules in pairs and combine the bandwidth therefore maximizing the capacity of the system. Note: It is recommended that, when using Dual Channel, you use identical memory sticks in pairs (frequency, capacity, of the same brand if possible).


Memory locations are noted as indicated below:

Dual Channel: [A1-A2] and/or [B1-B2]
  • A1 = 1st place (slot 1)
  • B1 = 2nd place (slot 2)
  • A2 = 3rd place (slot 3)
  • B2 = 4th place (slot 4)
  • *[A1-B1] = Group 1 on the motherboard.
  • *[A2-B2] = Group 2 on the motherboard.

Important notes

  • The following frequencies of memory stick are compatible with dual channel technology: DDR1600, 2100, 2700, 3200 and those with a higher frequency.
    • When using a single RAM stick then location A1 must be configured in single channel mode.
    • When using 2 RAM sticks of different brands then locations A1 and B1 must be configured in single channel mode.
  • To enable dual channel mode, it is necessary to use 2 (identical) RAM sticks in the A1 and A2 slots.
  • If you want to use 3 RAM stick of different brands, it is necessary to use 2 identical bars in the first group (A1 and A2) and the last one, of any other brand but with the same frequency in B1.
  • Finally, if you want to install a 4th memory stick in slot B2, it is necessary to use one similar to that in B1.
  • On motherboards having both 2 DDR2 ports and 2 DDR ports, only DDR2 ports can be used for Dual Channel.
  • This manipulation can be considered an inexpensive update, increasing the life span of your PC.

See also :

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