Hello, I'm Jewel with Kingston Technical Support and would like to offer our assistance. Our HyperX Fury memory is Plug and Play, so it should run at the highest speed supported by your motherboard and CPU combo. Since your motherboard supports 1866MHz memory, it may be that your CPU does not. Or it could have to do with the way the memory is installed in the motherboard, make sure the memory is installed as recommended by your motherboard manual. For further assistance, please contact 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 choosing HyperX.