It's a current vs cable thing. Every adapter I have seen uses two.
Maybe one with black connectors would help the aesthetics?http://www.newegg.com/Product/Product.aspx?Item=N82E16812887001
Also, I recommend turning your PSU over if your case has an intake on the bottom.
Cooler air for the PSU, and it's not "fighting" the bottom graphics card for air.