Turns out my laptop also shipped with AWCC (Alienware Command Center) installed which appears to override the DPM (Dell Power Manager) settings. I've changed the fan speeds in the AWCC profile.
How can I get it to save the DPM (Dell Power Manager) 3.9.0 settings? I'm trying to save the Thermal Management setting set to Cool.
Inspiron G15 5510, Windows 10, DPM 3.9.0, save changes?