Power Supply SFX PSU without no-fan mode (or at least optional)

Bakaban

SFF Lingo Aficionado
Original poster
Nov 13, 2020
120
110
I've been reading up on the recent 650-700-750-800-850 watt sfx psu offerings, and they all seem to now feature a semi-passive fanless mode. Some seem approach this by using internal temps as a tipping point for spinning up the fan, others seem to use psu-load as a measuring stick to turn the fan on or off.

Now ... I may have overlooked things, but I don't think I saw any that have a 'fan is permanently running, but mostly inaudibly slow' option. Which is what I am kind of looking for, since I'll be installing the psu in a very small case that'll no doubt be a bit of a hotbox and doesn't have a lot of options for good fan mounts (max side 1x 92mm, otherwise 4x slim 80 mm. Both options barely move air) so I kind of really want the psu to constantly be exhausting a bit of air.

Does anyone have any recommendations?
 

paulesko

Master of Cramming
Jul 31, 2019
415
322
If you want to go into the DIY territory, you can choose the psu you like the most, and then use an aquacomputer quadro with a temp sensor attached to the psu and set the fan setup you like the most, so you would control the psu fan with the aquacomputer quadro. Also some boards like the asus rog x570 i have a temp sensor input and you can control a fan header based on that sensor input (very usefull).
 

tinyitx

Shrink Ray Wielder
Jan 25, 2018
2,279
2,338
I take a quick look through Corsair, Seasonic, Cooler Master and Silverstone. Most SFX PSUs have semi-fanless mode and the trigger point is often somewhere from 15%-30% load.

However, I found 3 Silverstone SFX PSUs (>= 650W) that have constant running fan.
SX700-PT, SX700-G and SX650-G


Actually, I cannot think of a situation when the system is producing heat while the system load is low (thus, not triggering the PSU fan). Say, if the system is idling, I imagine the little heat produced would be easily removed by a single 90x25 or four 80x15 system fan(s). Frankly, if that amount of (little) heat cannot be handled by a 90x25 or four 80x15, I imagine the 92mm PSU fan would not help much anyway.
 

elvendawn

Average Stuffer
Nov 12, 2020
60
27
There is already other good info here, but if you are dead set on having a constant PSU fan, another option is to replace the internal PSU fan with something off the shelf and then plug it into your motherboard or fan controller of choice.

SFX you'll likely need a slim 92mm fan (like the Noctua NF-A9x14).
SFX-L PSU would need a slim 120mm fan (like the Noctua NF-A12x15).
 
  • Like
Reactions: Bakaban

Bakaban

SFF Lingo Aficionado
Original poster
Nov 13, 2020
120
110
I take a quick look through Corsair, Seasonic, Cooler Master and Silverstone. Most SFX PSUs have semi-fanless mode and the trigger point is often somewhere from 15%-30% load.

However, I found 3 Silverstone SFX PSUs (>= 650W) that have constant running fan.
SX700-PT, SX700-G and SX650-G


Actually, I cannot think of a situation when the system is producing heat while the system load is low (thus, not triggering the PSU fan). Say, if the system is idling, I imagine the little heat produced would be easily removed by a single 90x25 or four 80x15 system fan(s). Frankly, if that amount of (little) heat cannot be handled by a 90x25 or four 80x15, I imagine the 92mm PSU fan would not help much anyway.
Well, thank you for this very usefull input. Good man! And ... you kind of do have a point there. I forgot the sfx fan is 92 mm, thought it was 120.
 

MarcParis

Spatial Philosopher
Apr 1, 2016
3,616
2,705
Well, thank you for this very usefull input. Good man! And ... you kind of do have a point there. I forgot the sfx fan is 92 mm, thought it was 120.
I own SX-700PT, very capable SFX PSU.
Definitely it's audible even at idle (not silent, but quiet).

Otherwise if you want 120mm sfx-L psu, I recommend you SX-700LPT or SX-800LTI. They have both fanless mode at low load (till 150W approx).