I have an Fx 8350 OC'ed to 4.5 as of right now, using a Radeon Hd 7870 (which should be several models below the 770), and on BF4 ultra 1080 P I get around 45-70 fps, at least according to FRAPS.
I'd say something is bottle necking his system. With my gpu OC'd I get over 60 fps sometimes jumping up to 80 but never below 60.