Go get a set from Crucial.com and either sell off the old ram, give old away or shelve it.
Currently i am using samsung 4gb 1600mHz DDR3L 12800S-11-12-B4 + Micron 2gb PC3L-12800S-11-11-C1 two ram sticks. I want to upgrade to 12 gb Ram, so i m planning to replace micron ram with some 8gb ram. I want to know whether i should buy samsung 8gb ram with similar latency and 1600mHz or any other ram will give better performance? I want to know the ram that can give good performance with samsung 4gb 1600mHz DDR3L 12800S-11-12-B4. Also please tell me what no. "12" written in bold in first configuration depicts?

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