I would say an oc on that stock speed would make a world of difference. Seen it running o n a 970gtx at minimum 60fps but the guy has a clock of 4.3. You should be able to get a nice boost this way and 4.4 or more on air should be very easy. The patch will make a big difference too plus a new driver for you card. For Nvidia at least, performance seems the same as Far Cry 3.