Do you plan to overclock that CPU:Intel Core i5-3570K?
K series are special because they can be overclocked, but to get the most out of it you need a chipset that is designed for it. The H61 chipset for that ASUS mobo isn't designed for an Ivy7 Bridge K series CPU. Better look into a Z77 chipset based motherboard, and an after market CPU cooler as well. If you're not interested in overclocking than get a CPU:Intel Core i5-3570 (no K) and an H77 based motherboard.
Edit: Check out the HD 6870 vs GTX 460 the HD 6870 is much better and can be priced for around the same.