RAM itself is not dual channel, but it is how the memory controller actually handles it.
If you get a 2nd stick of the same RAM, and plug it into the appropriate slot, then it should run in dual channel mode.
By the way, dont expect too much of a performance increase while running your RAM in dual channel. In total, you will likely get about 1-5% performance increase. In this case you might notice it a little more, because you are adding more RAM.
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