RAM dual channel problem

[Guest]

So i got my new RAM sticks and motherboard, and i assembled my PC and then i check CPU-Z, and it said my memory is in single channel mode, so i got 4x2GB G.Skill Ripjaws 1600MHz and Gigabyte GA-Z77X-UD3H motherboard. So i read something about motherboard color codes etc, but my motherboard has a 4 black slots (same color)? So how i can dual channel my memory?

 

[rdc85]

U may need to set it manually from bios... (Check with mobo booklet/guide)