Do i need a nobreak or not? Also, another question.

[TheMirageOfDeceit]

I don't really know if I need a no break or not: some say I need, others say I don't. In the end, do I need a nobreak? I'm planning on getting myself the corsair RM650x if that matters.

Also, what exactly is an "active PFC"?

 

[CountMike]

If you have relatively stable power which doesn't go out often you don't need "Nobreak" but it's nice to have it. It continues to run devices on battery power for at least long enough to shut computer down in orderly manner and can somewhat keep input voltage at level, depending on type.
As for active PFC, https://cooltechpc.com/articles/power-factor-correction-pfc