Yes. Plenty good. Nvidia only requires a 450W PSU (minimum). But more would be recommended for a factory OC'ed version of the card. Plus you have an OC'ed CPU. Either way, you are good.
One caveat... if this is an older CX, they have a poor quality reputation. But if it has held out for you fine so far, I wouldn't worry. What gfx card did you have before?