Anyway, if we take 35% more than GTX580 into account and this link right here (1920x1200 resolution graphs). http://techpowerup.com/reviews/ASUS/...TX_580/27.html

135/75=1.8

We get 80% faster than Radeon HD 5870. Not entirely impossible seeing that this leap is pretty similar to Radeon HD 3870 -> 4870.