I think the issue with the motherboards is the more advanced power gating features in BD,on a module level inside the chip. It is kinda bad for present users to be unable to just buy Zambezi and slide it in their AM3 boards.But ,one can buy AM3R2 board later this year,when they appear ,and just use the X4/X6 until Zambezi comes along. Who knows,maybe Zambezi will even support 4 channels of memory too.