The first system will be much better but since your PSU has only one 6 pin connector, the GTX 560 isnt supported.
Thankfully there are still some good cards out there that need only one 6 pin connector.
The card i think you should get is the Powercolor HD 7850 2GB. http://www.newegg.com/Product/Product.aspx?Item=N82E168...
It's faster, newer,more overclockable, more power efficient and more future proof than a GTX 560 Ti.