4850 or 4870 at these prices

Ok, so I went to the local computer market today and unfortnately they won't be getting 4770s for months probably (only one shop had an X3 720 after all this time and that was a recent thing), so I'm left with a choice between a 4850 and a 4870. The former costs $135 while the latter is $219 (note: while I might be able to haggle a few bucks off, that's basically the price around these parts- I checked Newegg.com.cn and it's pretty much the same). Both would be the 1GB versions.

I'm sort of looking long term at this- I figure that eventually, once newer games and newer generations of GPUs hit, I could buy (by then) a used 47x0 and just do Crossfire to grind out another year or so on the card. So in that sense, while the 4870 currently doesn't outperform the price difference in terms of performance (50% price increase for 25ish% increase in fps), it might be a more frugal move in the long run.

Whatever GPU I choose, it would be paired with this.

AMD X3 720 BE (this will be purchased at the same time)

2GB DDR2 (an easy upgrade, if necessary)

Windows XP 32-bit

22" 1680x1050 monitor

of the 4850 and 4870 you mentioned get the 4850 because it will handle 1680x1050 for all games even crysis on high. Now of course the 4870 will be better. But if your are going to spend over $200 on a card then definetly go with the 4890 from newegg.com, they are worth the price and you will max any game at 1680x1050 with AA with the 4890. So 4850 if you want to save a few bucks, but 4890 from newegg if you want the best deal.