game crashes and fps story

[rocnogi]

 

interesting story
my video gtx 480 start to die from a week or so. now i use 4870 from my old PC .
and ... i must say . the fps drop is actually very low . and the game does not crash as before . the game freeze 2 times for a sec or two, but that's cuz the random fps drop .
so . gtx 480 is 3 times faster and stronger than 4870 . and still, the game is almost with the same quality.
i start to wonder . is the game made for AMD videos ? or ? i know that the game is basically a crap. badly made and so and so . but if the game run better with amd (like a lot better) why they just tell this .

 

is anyone have same exp with the video ? or if someone have nvidia and amd videos can test it ?