My problem is that pcpartpicker and other calculators say I dont need that much. In fact they say my 675 I already have is enough as is. It also has plenty of amps on the +12 so i am not worried there.
What I was planning to get was here: http://www.newegg.com/Product/Product.aspx?Item=N82E168...
If I dont need to though I will get something less powerful and less expensive.
Why do they say I need such a powerful power supply? Are they right or are they just playing it safe for liability reasons? Or are they simply trying to get me to spend more than I need on their product?
No you dont need the recommended PSU wattage. They put that recommendation there because they take into account that some people use poor quality PSUs that use cheap capacitors instead of Jap Caps. As long as your PSU is reputable then you'll be fine. If your still uncertain you can get an XFX, Seasonic, or Rosewill PSU they have plenty of greatly reviewed PSUs