I am going to upgrade to the 780ti from the gtx 660SC, I currently have the CORSAIR CX series CX600 600W psu. I read that the 780ti needs 42 amps on the 12v rail, mine says it is at 46 on the rail. I figured I would ask the people here if I will be alright, a 600W or greater psu is recommended for the new card.
I have AX760i + i7-4770K @ 4.5 1.4v + stock 780 Ti.
I was running LinX + MSI Kombustor at the same time and the maximum power output to the PSU was around 510 watts (monitored in Corsair Link); the CPU itself is 170 watts TDP at that time (monitored in RealTemp | TI)
But that's the peak power output with GPU "Boosted" very much; In a couple of minutes running the same stress test power draw drops to around 450 watts.
So If the CX600 can give ~550 watts on the 12v rail it will handle an overclocked Haswell and 780 Ti well. In my system during gaming I think power draw is much lower, about 350 watts, which would fall to the safe 58% of what your PSU could handle (and that's especially good, cause PSUs best efficiency is around 50%)
So unless you have a greatly overclocked 8-core AMD CPU (like 5 GHz) I think you'll be fine with CX600