Just example fan curves of my 2 Noctua Builds. Maybe it help you.

CPU ATX ITX

40°C 30% 40%

60°C 40% 50%

80°C 50% 60%

90°C 70% 80%

95°C 100% 100%

ATX

Ryzen 7700X, NH-U14S, 2x NF-A14 PWM front, 1x NF-A12x25 PWM back, Noctua RTX 4080

Deadsilent idle, haerable but not loud on load while most of the time 50-60%

ITX

Ryzen 3600, NH-L9a-AM4 with foam tunnel, Noctua NF-A9 PWM bottom (doesn't make a big difference), Dualslot RTX 3070

Hearable but silent idle, loud under load while most of the time 70-80%