Neither sha256 (bitcoin) nor scrypt (litecoin) mining uses floating point operations. AMD cards are faster because they are built with more, simpler "cores", c

Neither sha256 (bitcoin) nor scrypt (litecoin) mining uses floating point operations. AMD cards are faster because they are built with more, simpler "cores", compared to Nvidia's fewer, more complex "cores". Mining benefits from the increased parallelization and doesn't benefit from Nvidia's "fancy" "cores". For sha256 mining, AMD cards gain an additional advantage by supporting a bit rotation instruction that Nvidia cards do not.