You said you dont need anything too powerful, but then u select the 3770k and the ASUS SAbertooth mobo.
if your intentions are just gaming you can save some cash by getting a 3570k.
You can also save more money and get the
Asrock Z77 Extreme 4 mobo.
GPU- You wont need 4gig VRAM unless you run some crazy resolution, even then you would be better off getting something like the
7970GHz edition.
HDD- I cant recommend the seagate HD instead get the
WD caviar black. IF you are just using it for storage you can get the
Caviar Blue
PS- Not sure about that one, it is definitely too much for a single card system, go with something more along the lines of this
Seasonic Its fully modualr so your system will look cleaner with less cables and is made by the best PS manufacturer there is.
SSD- the one you have is fine but a lot of people have been suggesting to get the 840 series over the 830, such as this
Samsung 120g SSD