Help Me

okay so i have a AMD3 8120 with a UD3-990 fx Gigabyte motherboard.

8gb/s of Kingston ram 700w power supply. Now what i need help with is choosing what card i want.

So here is my options

                1) EVGA NvIia GTX550ti (2 in sli)

                   2) XFX Radeon 7870

                      3) ASUS Geforce GTX650

7870, unless you have a use for CUDA.

7870 or 7870 xt