9970 = Titan / 9950 = 780 / 9870 = 770 / 9850 = 660 / 9770 = 660ti / 9750 = 660 / 9730 = 650ti boost edition... 99xx = 512 bits 4 & 8 gb 98xx = 384 bits 3 & 6 gb 97xx = 256 bits 2 & (4 gb cheap memory)