Speaking to Gainward at CeBit, it seems they plan to wrestle XFX for the title of fastest clocked GeForce 7900 GTX. With XFX's XXX Extreme coming in at 690MHz, 40MHz over standard, Gainward are shooting for something even higher. Still in development and with clocks yet to be finalised, Gainward are currently aiming for around 720MHz core and 900MHz mem.
http://www.hexus.net/content/item.php?item=4927