this. 35~FPS @ 1024x768 in crysis with a 5750 is pathetic :thumbsdown:
ed: OP, if you havent built the comp yet, then it isnt a fair comparison. your 5750 looks to be unde rperforming really bad for some reason, my 9800GTX, which is give or take about as fast depending on the game, was able to play it medium/high with no AA @ 1680x1050, avg 35FPS, with a lot of settings tweaking. ATI cards are generally a bit slower in crysis than nvidia cards, but were talking about literally a doubling of resolution here, so i suspect that the rest of your system is just really old and slow, or there's something else going on.
to answer your question specifically, if you read the 5870 reviews for when it came out, on AT here, their test bed is a bit slower than mine (+/- 7-10%) without the CPU overclocked, so if you look at the reviews you will see where one scores. as far as 1024x768, a single 5870 should walk all over that.