v-sync fps issues

Hi, I understand that your supposed to turn on V-sync and G-sync if your frames are high like over 100 FPS and your monitor is 60FPS. But I am not sure on, do I have to enable V-sync/G-sync on my monitor, Nvidia and on my game all at once meaning I have 3 V-sync/G-sync enabled. As I can enable...

I recently got this card and I am using MSI afterburner to set a fan curve for it (I've done this before so I'm not new to this) and I've set the fans to run at 0% at below 30degrees. HOWEVER, the fans are currently spinning at a minimum of 34% at 24degrees, not 0%. Can anyone explain why...