http://www.tomshardware.com/us/#redir ... the best site... ok it goes like this:
1. search on tomshardware on CHARTS, GPU charts select a game, and look through them
2. go to pcgarage.ro or emag.ro (pcagarage got lower prices-ROMANIA ONLY)
3.search the GPU u found there and see the price.
it's like this: nVidia got gtx 280/260s(>20 milioane lei vechi) which are top class but ATI HD4870x2 is better than them, and it's kinda cheaper in romania. well, you choose.
you can check this one too: http://www.tomshardware.com/reviews/radeon-geforce-graphics,2086-7.html
P.S.: it's : nVidia. The way it's meant to be played. (ex.:Unreal Tournament). and nVidia has better drivers. trust me. and from popularity, if you trust romanian guys, you could end up in a fiesta saying it overruns a mercedes. GT*O!
Hope i helped,
MiNiMaLsAnItY