I guess I was confused by your original post. Personally, I would get the gtx 760, but the game bundle available with the 7870 is really nice if you do not have those titles. The performance of the two will be very similar - coin toss time!
Buy the best SINGLE card you can afford. Either of your duals above would run you ~$500. Check into a gtx 770 or 680 or a radeon 7970.
The thing is that the best card i can afford is a gtx 760 that's why i'm asking, that way i would know if it would be a good idea to buy one and then way to buy another because it will take along time for me to buy even one of them
I guess I was confused by your original post. Personally, I would get the gtx 760, but the game bundle available with the 7870 is really nice if you do not have those titles. The performance of the two will be very similar - coin toss time!