What should my Smart Fan settings be?

In BIOS, Smart Fan has the following options:

Smart Fan target:

40c
45c
50c
55c
60c


CPU min. fan speed %:

0.0
12.5
25.0
37.5
50.0
62.5
75.0
87.5

CPU Fan PIN select

3 PINS
4 PINS

What should I put these settings at? Or should I not use Smart Fan at all?

I also have Speedfan and could use that as alternative. Would you recommend that instead and if so what settings should I set Speedfan to?

I don't know what I'm doing so help is appreciated.

Thanks.