Fans connected to PSU, how to quiet them?

ruki.deathvoice

Prominent
Aug 14, 2017
10
0
510
I got three (male?) molex fans, directly connected to my PSU. Is there any possibility to let them run more quietly? They run at 100% all the time and I can't afford new PWM fans this month. Please help!
 
Solution
No no, your fans are just regular 3 pin fans. They are then at some point in the cabling plugged into the molex, which connects them to PSU. All fans have those regular 3 or 4 pin connections. Trace the fan cable back all the way back to the fan. You'll find where it turns into just a regular fan cable. It'll look something like this https://s17-us2.ixquick.com/cgi-bin/serveimage?url=http:%2F%2Fwww.corsair.com%2F~%2Fmedia%2FCorsair%2FFAQs%2FPSU%2520Paper%2520Clip%2520Test%25203.png&sp=8d56600a5d1cfc76e9e739f409242f63
without the 2/3 pin cable in the middle.

ruki.deathvoice

Prominent
Aug 14, 2017
10
0
510


I use a MSI B350 PC Mate. 3 fans connected to the PSU, one in the back and two in the front.

 

Sedivy

Estimable
You mobo specs list:
- 1 x 4-pin CPU fan connector
- 1 x 4-pin water-pump-fan connector
- 4 x 4-pin system fan connectors
- 1 x 4-pin RGB LED strip connector
(https://www.msi.com/Motherboard/B350-PC-MATE.html#productSpecification-section)
meaning you have plenty of fan connectors.
Unplug your fans from the molex connection (shut down your pc first of course), then connect them to the 4 pin system fan connectors (download manual here https://www.msi.com/Motherboard/support/B350-PC-MATE.html#down-manual, then go to page 22, they'll be labelled SYS_FAN 1 through 4).
Download from https://www.msi.com/Motherboard/support/B350-PC-MATE.html#down-utility
a utility called command centre. You technically don't need it but it's nice not to have to go back into bios to adjust your fans every time you want to nudge the curve up or down.
Anyway, first after you connect the fans, load into bios then from there, select each of the system fans (don't touch the cpu fan), and select DC instead of PWM. You can adjust temp/RPM curves yourself or let system optimize it. Then once you start up, start the command centre, and from there you can access those fan curves and further adjust if you want them lower/higher while you're gaming or doing stuff. Just be aware that for those adjustments you apply in command centre to stick, command centre has to be loaded, and whatever profile you created, also has to be loaded. Otherwise it just reverts to bios settings.
I'd also get something like HWMonitor which will let you keep an eye on system temps and rpm of all the fans, so you have better overview when adjustment is needed.
 

ruki.deathvoice

Prominent
Aug 14, 2017
10
0
510


Thanks for all the effort you did there, appreciate it! I'll remember it for the future and plug my new fans there when I get some. But my problem is that my fans have these big molex plugs and i can't connect them to my mobo. They're probably cheap ass case fans and can be only connected to the PSU. Is there any kind of adapter I can use to plug them to my mobo or maybe just regulate the voltage while the fans still get their power from the PSU? I'm a noob, sorry.
 

Sedivy

Estimable
No no, your fans are just regular 3 pin fans. They are then at some point in the cabling plugged into the molex, which connects them to PSU. All fans have those regular 3 or 4 pin connections. Trace the fan cable back all the way back to the fan. You'll find where it turns into just a regular fan cable. It'll look something like this https://s17-us2.ixquick.com/cgi-bin/serveimage?url=http:%2F%2Fwww.corsair.com%2F~%2Fmedia%2FCorsair%2FFAQs%2FPSU%2520Paper%2520Clip%2520Test%25203.png&sp=8d56600a5d1cfc76e9e739f409242f63
without the 2/3 pin cable in the middle.
 
Solution