Where do you get these $80US 2900XT and X1950XTX options? Those make me curious. As far as "bang for the buck" goes, if you really could get the 2900XT (and not a pro or GT) for that much, then it'd actually best the price-performance ratio of the $170US 4850.
But failing that, out of what you listed, the 4850 trumps all the others in performance hands-down, especially if you enable AA.
Depending on what that "650 watt psu" is, i.e. if it is actually a 650W PSU rather than merely being labeled like one, in your place I would choose a 4850.
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Reply to jtt283
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