Welcome to the forums, newcomer!
Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.
Off a crude look up, BIOS>Tweaker>Memory Clock Mode>Change from Auto, hit Enter, you should see a new window with XMP showing in the window.
If you don't see anything XMP in that window, the ram you have doesn't have it or you're lacking the latest BIOS version.