I currently have 6 gig 1600mhz of DDR3 ram in an asus p6x58de mobo in slots A1 B1 C1 . The manual says I can add another dimm to slot A2. I want to add therefore another 2 gb 1600 mhz dimm to slot A2 to make a total of 8 gigs. Question.. Does it need to be the same manufacturer of RAm and exactly the same serial numbers as I have now which is Kingston Hyper x genesis KHX1600c9D3K3/6gx ???