Hi, I'm Jewel with Kingston Technical Support and would like to offer our assistance. Technically, your CPU only supports up to DDR3-1600 MHz but since it is unlocked it may be able to support the higher memory speed but is not guaranteed. First, thing to check is to make sure the memory is installed in the proper slots. The manual for your motherboard recommends slots are A2 and B2 or A1 and B1. If you are fully populating try it with two and see if that makes any difference. For any further assistance, please call us at 1-800-435-0640 (USA and Canada only) M - F 6am - 6pm PT and I or another available Technician will assist you.
Thank you for selecting Kingston as your upgrade partner.