Computer build (first attempt alone)

Hey guys,
so i have finally built up a little bit of confidence to attempt a computer build on my own and i would like some opinions on whether the pieces will be compatible together and any advice on switching some components (I'd really like the price to stay about where it is or down a bit) but i have a few extra if NEEDED.

A small note on my needs: I am a pc gamer but for a very specific genre, i, on occasion will play a shooter (perhaps farcry or borderlands) but i will regualry play online games such as World of warcraft, starcarft, league of legends, DOTA. I do play enough shhoters thati felt somewhat justified in a better GPU.

That being said i am always looking to improve and could really use the advice so here iswhat i landed on:

CPU:
Intel Core i3-2120 Sandy Bridge 3.3GHz
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

GPU:
EVGA GTX 660 2GB
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

case:
NZXT gaurdian
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Power supply:

OCZ ZT Series 650W Fully-Modular 80PLUS Bronze High Performance Power Supply compatible with Intel Sandy Bridge Core i3 i5 i7
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Motherboard:
Intel BOXDZ75ML45K LGA 1155 Intel Z75 HDMI SATA 6Gb/s USB 3.0 Micro ATX Intel Motherboard
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

RAM:
CORSAIR Vengeance 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Low Profile Desktop Memory Model CML8GX3M2A1600C9

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Thanks again for the help guys!