Which one for 1080P max? Say I would want to run Metro: Last Light, read some bench marks which favors the R9 280X. Do not know if I am overkill, here can I step down to the 7950 or 270X and still hit good FPS at high settings? Would be paired with a Haswell i5 4670, no OC and a 750W PSU. If I want to go Crossfire down the road, do I have the PSU to handle dual cards?