Don't buy the i5 2500, either go with the i5 2500k or the i5 2400. The 2500k allows you to overclock your CPU while the i5 2400 does not. the performance difference from the 2400 and the 2500k is not noticeable. You can also go with this motherboard: http://www.newegg.ca/Product/Product.aspx?Item=N82E1681...
Motherboard: MSI PH61A-P35 (B3) LGA 1155 Intel H61 SATA 6Gb/s USB 3.0 ATX Intel Motherboard with UEFI BIOS
Memory: Wintec AMPO 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 Desktop Memory Model 3AMD31333-4G2K-NHR
I'm really surprised that no one has noticed that an H61 won't be able to handle a 7970, and that 550W will be very underpowered for that setup (Sapphire recommends minimum 600W for 7970) . Plus having 4GB 1333 is pretty redundant anymore.