Connect usb 3.0 to motherboard

[zeefrog]

I have a Rosewill Future mid-tower(Gaming ATX) that came with two usb front 3.0 ports installed. The motherboard is an Asus Sabertooth P67. I need a 20 pin cable to connect the usb 3.0 ports to the motherboard. I belive it would be similiar to the letter "Y." Any help on where I could find this cable is greatly appreciated.
Rosewill was no help.

 

[h3sham]

http://www.bitfenix.com/global/en/products/accessories/internal-usb3-adapter

 

[nikorr]

http://www.newegg.com/Product/Product.aspx?Item=N82E16812176003