What resolution do you play at? a GTX 560 will not run BF3 on ultra, though it will cope with a none modded skyrim.
560Ti is a much better option http://www.newegg.com/Product/Product.aspx?Item=N82E16814125363
its $220 but worth the money, the 560 isnt.
For BF3 on ultra you will need a 570 at least, though the OC'ing abilities on the 560Ti's will get you damn close @ 1920x1080