Enter BIOS/UEFI and adjust fan curves or fan control settings
Use motherboard software from the manufacturer
Use third-party fan control software
Connect fans to PWM or DC headers on the motherboard
Use a fan controller hub or manual fan controller
Check and set fan mode to PWM or DC correctly
Clean dust from fans, heatsinks, and filters
Reapply thermal paste if temperatures are high
Improve case airflow with better fan placement
Replace fans with quieter or higher-quality models