So I'm finishing this build for my roommate. I had already ordered 8 gigs (2x4gb) for his computer but when I bought his mobo newegg threw in an extra 8gb stick from gskill. So question is, how much of a performance hit will his computer take if he runs a single channel 8gb stick vs dual channel 4gb sticks? If it's miniscule I'm sending the 2x4's back. Thanks in advance!