Build Suggestions/Feedback

I'm building a new PC mostly for gaming.

Here is my build so far:

HDD - Seagate Barracuda ST1000DM003 1TB 7200 RPM 64MB Cache SATA 6.0Gb/s 3.5"
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

RAM - G.SKILL Ripjaws X Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

PSU - Rosewill Green Series RG630-S12 630W
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Mobo - MSI Z77A-GD65
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

CPU - Intel Core i5 2500K
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

GPU - Probably an HD 7870 or a GTX 660.

Fan - COOLER MASTER Hyper 212 Plus
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

I mainly just have questions on my PSU and Mobo. The PSU is fairly cheap and just wanna know if it's of good quality.
As far as the motherboard goes, it seems a bit pricey. Is it alright or should I get an alternative?

If you need any clarifications, let me know thanks!