That PSU you listed is not exactly up to snuff.
"? Run, efficiency should be >85%, you've gotta pay for all that wasted electricity after all.
No PFC and two 80mm fans make me feel like I'm back in the 1990s,...
Go for something 80+Bronze certified at the very least, like the XFX Core Edition 550W or PC Power & Cooling Silencer Mk III 600W
If you can afford it, choosing a 80+Gold capable device can't possibly be a bad move. Rosewill Capstone 750W is very reasonably priced.
You already know about nVidia, right?
Grab the most powerful AMD card you can afford since you'll only be able to use two cards with that mobo.
If you find mining profitable, you can always purchase a second card later on.