As we explained, some motherboards allow you to increase the memory clock separately from the CPU external clock, which is the best option for achieving a high overclocking.

There are two ways of configuring the memory clock on asynchronous motherboards: using predetermined  fixed value or typing in the clock you want. This option will depend on the motherboard model.

The motherboard we shown on Figure 3 the memory clock options are fixed. As you can see, you can only choose the memory clock from a predetermined list of settings. This is not the best case but it is better than not having any memory overclocking option at all.

The best scenario is to have a motherboard where you can type in the memory clock you want, like you can see on Figure 5. Usually you need to change a configurarion called "DDR Timing Setting", "Clock Control", "System Performance" or similar from "Auto" to "Manual" in order to change the memory clock.

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Figure 5: Memory clock configuration.

As we mentioned before, you will need to increase the memory clock, save the configuration, reboot your PC and test if the memory overclocking worked or not. If it worked, you need to repeat the process again trying a higher clock. If not, you need to repeat the process again trying a lower clock. You will need to repeat the whole process several times until you find out the maximum clock rate your memory accepts.