GX2 does "better" performance wise in games (up to around 20fps more) but is also the more expensive card, with slightly less image quality as well (debatable). DX10 cards will come out in a few months...but its not advisable to get one till at least a few months into 2007.
Recommendation: 1950xtx unless you are going to be playing on a very high resolution where the FPS will make a difference.
hes asking about a normal GTX or an X1950XTX not a GX2. Go with a x1950xtx if you really want to spend the money. I'd get an x1900xt and save myself $200
Neither one XD lol. Do what alot of people are doing & just wait until the DX 10 cards drop & are out for a few months. Unless you plan to buy a card now, sell it, & then buy an DX 10 card =). I would save the trouble though.
Getting a DX10 card right when they are available is kind of useless IMHO. You need more than just the capable card to get the benefit of this.
1. Vista (Available in Jan 2007 if we are lucky)
2. DX10 card (prob avail prior to Vista launch)
3. DX10 capable games (which may be longer that a few months into 2007)
so what is the rush?? I have yet to figure this out.