For that PSU you will need two 6 pin PCIE connectors.
The following PSUs will do the job:
XFX TS 550W
Seasonic S12G-550
The above PSUs have the required connectors for your video card. For future reference, go onto Nvidia's site and look for your video card, look in specifications and it will tell you the requirements. Then find your PSU on the company site and it usually has the connectors that come with that PSU