So upon the first boot of my first pc build, I noticed that my RAM which is 16gb of corsair's vengeance pro series 1866 mhz was only running at 1333 mhz(according to the msi 970 gaming BIOS). I don't know exactly how the RAM works does the frequency increase as i start to run more demanding programs or do i have to manually "overclock" the RAM to 1866 mhz myself in the bios?