Okay so I currently have a gigabyte ga 990fxa-ud3 rev 4.0 MoBo. While looking at the Ram compatibility list for it, I notice, in red print, it says something about Memory speed 1866 and up will only support 1 dimm per channel when using an am3+ cpu. I kinda understand what the means, basically saying if I used 1866 memory i would have to install it in slots 1 and 2 of the mobo, or 3 and 4 of the mobo, basically rendering the other 2 slots useless. If i am wrong on that someone please tell me. Other than that Im also asking would it be better to use 1600 memory in 1 channel and have the other channel for future (getting 2x4 gb btw), or go ahead and do the 1866 in 1 slot of both channels, rendering the other slots of both channels useless unless I take the 1866 out. If this was confusing plz ask me about anything I wasnt clear on.