First timer asking about ram

Hi guys just built my first gaming pc (thanks to everyone on here who helped me) I have 3600mhz of ram and while I was in the bios I noticed that the ram was only showing as just over 2000 I downloaded cpu z and they displayed the same. So I went into advanced settings and it says I can change it to 3600mhz. So should I change it or leave it? Thanks in advance