fan ramps but never drops

Wing-Man · 26 Mar 2022 at 17:42

Evening all, the Fan on my PSU Ramps when underload, and some times when not under load.
But ever way ones the Psu Fan ramps it never go's back down until i power cycle the system.

is there a fault? is it someing i can RMA for, and dose it need to be RAM'ed(could it be a fault that becomes a bigger broblem)

PSU - https://www.overclockers.co.uk/lian-li-sp750-sfx-modular-80-plus-gold-power-supply-ca-79g-ll.html
I got it from OcUK

pastymuncher · 27 Mar 2022 at 19:54

The inside of that psu is very cramped and has a pair of tiny heatsinks so with a 92mm fan it's going to heat up pretty quickly. I read a review on Anandtech and they recorded 1.2 degrees C on the secondary heatsink while hotbox testing. basically the heat generated overpowered the fan and once maxxed out at 3000 rpm it couldn't control the heat and it just kept rising. I suppose the best you can do is ensure it get's as much unrestricted cool air as it needs to suck in. The review said that the fan doesn't even kick in until 60 degrees C so it shouldn't be coming on when the system is idling. Maybe there is a fault with the fan controller in the psu.

Wing-Man · 28 Mar 2022 at 12:10

But in there cool testing at 25c the psu is fine, my room is around 22c and my case O11 mini as the psu in a separate part of the case so the cpu/gpu shouldn’t be affecting it too much.

I removed the filter that’s next to the psu f or better air flow. I will see how I get on

let not forget when the psu run away it was tested in a room at 45c but the temp went up to 47c and the psu was run at max watts/amps. My problem is in a room at 22c ish and idle power draw

pastymuncher · 28 Mar 2022 at 18:56

pastymuncher said:
The review said that the fan doesn't even kick in until 60 degrees C so it shouldn't be coming on when the system is idling. Maybe there is a fault with the fan controller in the psu.