That's just stupid IMO.
They make it so it scales SLI 20% better on 790i boards, which is excellent.
BUT. They're only DDR3. That's stupid.
The only type of DDR3 that's remotely affordable is DDR3 1333MHZ. At stock speeds, it performs just as well if not a bit worse then DDR2-800.
You'd have to OC your 1333 to 1600mhz or spend a grip on DDR3 that runs higher then it to tell a difference between the two.
Stupid stupid stupid stupid stupid.