Which graphics card is better?

[marcus]

My current graphics card is:

GeForce GTS 450 with 4GB of video ram.

It can run games like battlefield 3 and Skyrim on full settings but it is not as good as i would like it to be, and i want to upgrade it. The graphics card i want to buy is a GeForce GTX 580 with 3GB of video ram.

If i bought this new graphics card, would it make much of a difference?

Thanks.