I have a decent rig, AMD 6100fx, As Rock 990fx Extremem 3 Mobo, Gskill 8gb Ripjaws, 1 X 60gb Intel 520 Series SSD, 1 X 120gb Patriot Pyro Sanforce SSD, 1 X OCZ Agility 3 120gb Series SSD, 1 X 2tb Seagate 7200 HDD, Antec H40 Watercooling, a Antec Earthwatts Bronze Rarted 750w PSU, NZXT Phantom Case and 2 X EVGA 660ti's Superclocked (or soon to be two!)... Wondering if the Antec i have is good for all that. Hopefully it is!
Yes it will be fine. Here is Guru3Ds power supply recommendation:
GeForce GTX 660 Ti - On your average system the card requires you to have a 450~500 Watt power supply unit.
GeForce GTX 660 Ti SLI - On your average system the cards require you to have a 700 Watt power supply unit as minimum.