I had build a custom PC, Asus M5a78L-M/usb3,AMD FX 8150, 8GB 1600mhz Kingston Hyperx Ram, Nvidia 650 Ti, Cooler Master 600 Watt PSU, but in CPU-Z its only showing 667 mhz i.e., 1333mhz as it should be showing 800mhz. i would be very grateful if someone could help me out of this problem.
Download the motherboard manual from Asus support.
(page 2-11) Change Memory Clock Mode from [Auto] to [Manual].
(page 2-12) Set Memory Clock Speed to [800MHz].
(page 2-12) Set the first four DRAM Timing numbers.