To get the maximum performance for your PC for gaming or rendering and may be for other thing, it always recommended to use Dual Channel Ram module setup. First you need to validate that your Mobo(Motherboard) support dual channel ram setup or not. Most of the latest motherboard from Msi, Asus and other companies support the dual channel setup.
To fix the issue, first you will need to check that the cooler on your CPU should not be tight. Loose the screw of your cooler. Then read the ram setting in your Mobo. If you installing single ram then it should be in second slot. If two for dual channel then it should be in second and fourth. Check the below setup image.
Enable the XMP profile
You could enable XMP profile that help to overclock the ram automatically. You can set voltage and Mhz manually. You should confirm your recommended volt as it could damage your ram or may lag your PC. After setting up the XMP profile, your dual channel ram setup may start to work.