Beware: I bought a EVGA 850GA (Gold). Eco mode ON has the FAN OFF all the time. It does NOT turn fan on even when Intel I5 12600K and RTX 3080 12G are pulling over 450W for over 5 minutes. The fan is OFF in ECO MODE, regardless of system load/duration. The PC then crashed. Happened 3 times. PC does not crash with ECO OFF. Cannot feel the FAN come on in ECO MODE.
I'm replacing it with a 850 P6 (Platinum), which has the same ECO MODE button. I'll see if my particular GA had an issue or if ECO MODE never turns on the FAN on any model. Not supposed to work this way.