stick with the x850 pro, the x1600 may have 512mb which is pointless for a card that cant perform 2 the max. the xtra ram is a waste. Even if sm 3.0 comes out anytime soon, the x1600 will perform just like a 9800 pro. Stick with the x850 pro, for there will not be any games running on sm3.0 so enjoi the games and glory for the next year or so. The 512 mb of ram on the x1600 is just to get ppl to purchase a card that will not perform to your specs. Like I say stick w/ the x850 pro. If sm 3.0 is a must have 2 play future games. go w/ the x1800 series or better the x1900 series, truth is, U need 2 have serious cash if planning 2 purchase these cards.
-good luck- 😀