They just came out with DDR3, DDR4 is a LONG ways away.
Unless your talking about a video card that uses GDDR3/GDDR4. The type of RAM a video card uses has nothing to do with the motherboard. Motherboards will say DDR2, but thats for the type of RAM that it's compatible with, not the type of RAM thats on the video card.
They have several new LGA775 crossfire motherboards that support both DDR2 and DDR3 RAM.