Have 6GB of Corsair TR3XG1600C9 running at 1600MHz. Installed another 6GB of the same memory and the bios only see's 8GB.Disable th XMP setting in the bios and the memory runs at 1066MHz and i get the full 12GB.Anyone any thoughts on why. Bios is F6. Bottom line- I can only run 8GB at 1600MHz. Regards Pete.