It draws significantly less power than the 6990. So it's basically matching the 6990 @607 clock and lower power draw. With a proper OC it should easily beat it even if the 6990 is OC'd.
Obviously the massive downclock is to meet specs.
Obviously the massive downclock is to meet specs.
A pair of GTX570s is cheaper, and for the most part as good if not better.
(not me, i'd like to point out)