4 pin Fans

[Kurma]

Hello Guys, 

I have a bit of a luxury problem I got myself a node 304 case on ebay and the previous owner replaced the stock fans with noctua (I know great taste 😄).

But they are all 4pin. My topton mobo only has two fan headers one 4pin for the cpu fan and one 3pin for case fans.
I tried putting the fans with a splitter on the 3pin case fan header. This results in max speed fans (I can not change that in the bios as far as I can tell), which is too loud for my tiny apartment.
So I unpluged the cpu 4pin header and now put all my fans on them. It looks like the cpu fan always spin meanwhile the noctuas only hit the fan 😉 ones the speeds goes higher. Is this a bad Idea or is this fine for a low power server built?

[Kurma]

Hey, so I think the topic name is pretty bad but can not change it ....
I noticed that my fans are often speeding up for short bursts. Is this because the temperature is around or threshold or is it likely due too overload?

[Zer0Log1c]

I believe it'll depend a bit on your specific motherboard and what its settings are; but normally, that CPU Fan header will be able to be adjusted fan speed based on the CPU temperature reported.

I'd expect that the fans all ramp up as your CPU hits a high utilization and then they'll slow back down as soon as it has either hit a lower steady state or finished its work. 

As for whether or not it is a bad thing, I don't think you should have any issues. I have once run into a problem with a motherboard burning out a Noctua fan (twice back to back actually) but I believe that was down to the Pump header that I was using pushed too much amperage (presumably) through the fan. I don't think a single splitter should put anything at risk.

Edited December 10, 2024 by Zer0Log1c
typo

[Qbert]

1 hour ago, Zer0Log1c said:

I believe it'll depend a bit on your specific motherboard and what its settings are; but normally, that CPU Fan header will be able to be adjusted fan speed based on the CPU temperature reported.

I'd expect that the fans all ramp up as your CPU hits a high utilization and then they'll slow back down as soon as it has either hit a lower steady state or finished its work. 

As for whether or not it is a bad thing, I don't think you should have any issues. I have once run into a problem with a motherboard burning out a Noctua fan (twice back to back actually) but I believe that was down to the Pump header that I was using pushed too much amperage (presumably) through the fan. I don't think a single splitter should put anything at risk.

This.

Also some bios allow you to tune the fan profiles without an os application.

[Zer0Log1c]

2 hours ago, Qbert said:

Also some bios allow you to tune the fan profiles without an os application.

Yes! Forgot to mention that the bios should have some degree of fan control to it. Hopefully it'll be PWM (fine grain) control since it's a four pin header for the CPU fan.

Even three pin header can have speed control though, but it's a lot closer to low/med/high from my experience since it'll use voltage modulation to change fan speeds instead of of PWM