Nepton 140xl fans

Wanted to ask at around what temp do the fans for a Nepton 140XL start kicking in. I have reached 70C on my FX-8350 and they still aren't spinning please help. Thank you

I plugged mine into the CPU PWM fan on my mobo, and set it to like 1.5 PWM setting or something like that. they spin around 800-1500 RPM depending on temp. i get as low as 17C idle(overnight) to around 50C typical load... but they should immediately startup upon boot.

I did that after some contemplation and it works, thank you for the advice anyway.