The info I presented was for anyone interested, especially Ironsounds who indicated in his response that all would run in single channel, and to back up MadMatt30's statement
"^ not necessarily - its board dependant - I've seen plenty of boards run 2 sticks on channel a & a single stick on channel b in dual channel mode if the channel total is the same.
Saying that I'd just sell the 2x2gb sticks & buy a 2x4gb pair to play it safe personally."
I agree about mixing DRAM and probably point it out to people at least a half dozen or more times a day, it's covered in the Fiction part of that article, Item 2:
http://www.tomshardware.com/reviews/ddr-dram-myths,4155.html