Phenom ganged and unganged modes

[justapost]

Im going to push all the motherboard vendors I talk with to reword unganged single channel to dual channel 2x64bit mode on the boot screen, this simple misrepresentation is going to cause no end of RMA requests for all the memory manufacturers.

Or

single dual channel 1x128bit for ganged and
dual single channel 2x64bit for unganged mode

AMD's K10 spec says there is a new channel interleaving option beside chip/bank interleaving.
Can channel interleaving be activated via the bios and does it have an impact on performance?