That power supply is WAY OVERPOWERED for a single card setup. Get a 650 Watt corsair, or a 550 Watt Seasonic and save $30. This combined with the $20 savings from the non-K processor should be enough to bump you up to a 570 GTX. Which will definetly help playing borderlands 2.
If you have money to spare, I would further upgrade your video card to a 680GTX.
I couldnt see your link to the motherboard, its broken. So I cant tell you if your mobo is compatible. But with your needs (especially the need to save money so as to spend more on the graphics card) I would get a p67 or z68 micro-ATX board for under $100. Make sure it has pcie 3.0, usb 3.0 and Sata III.