So I decided to get the Radeon HD 7970. However, today when I was picking up my monitor, I asked whether they had the 7970 and the guy said no. Then I asked if he had the Corsair CX 600 Modular and he said that he did but it would not be enough for the 7970. He said that I needed at least 750W which I highly doubt. I just wanted to make sure on here. Thanks!
Here is Guru3D's power supply recommendation:
Radeon HD 7970 - On your average system the card requires you to have a 550 Watt power supply unit.
Radeon HD 7970 Crossfire - On your average system the cards require you to have a 750 Watt power supply unit as minimum.
If you are going to overclock GPU or processor, then we do recommend you purchase something with some more stamina. http://www.guru3d.com/articles_pages/amd_radeon_hd_7970_review,8.html