GTX 660 Ti 2gb Vs. HD 7950 OC 3gb

[snagov]

Hi, i would like change graphic card. I have 2 options, which is the best option for CloDo?

Option a: Sapphire Radeon HD 7950 OC 3GB GDDR5 950 MHz

Option b: Gigabyte GeForce GTX 660 Ti OC 2GB GDDR5

My specs:

- AMD Phenom x4 3,2 ghz
- MB Gigabyte GA-970A-D3
- 2 x 4gb Kingston 1600 mhz.
- Packard Bell Viseo 230 1920x1080 60 hz.
- Saitek X52 + Saitek Pro Pedals
- Thermaltake Power Supply 700w

Thanks.