[SOLVED] CPU fan runs at 100% after closing any game

Solution
It seems BIOS using RPM values instead of PWM percentages. I've lowered PWM percentage to 1, 3, 5% and fan runs on about 1400 RPM. Is there a way to adjust PWM and RPM values?

PWM and RPM are tied to one control, since PWM dictates the percentage, as you are aware, and the RPM by the fan itself.

There's a lower limit to how slow a fan model can spin. Bigger fans can run as low as 300 RPM, a typical 120mm would probably run at 700-1000 RPM depending on model. At lower PWM percentage the fan would just spin at its minimum speed. Voltage (3-pin) controlled fans would simply stop spinning beyond its lower threshold.

Out of curiosity, is the fan fully plugged in? I had a similar issue with my GPU AIO that turns out my 4-pin...
to help properly diagnose any system problem, your COMPLETE system specifications need to be posted.

the second image is of the CPU_FAN header stats.
the fan curve profile is it's "curving" line going from ~18°C\1800rpm - 90°\13500rpm.
you may want to try setting a new custom curve since the current one doesn't seem to be functioning or reading correctly.

i always start with 25% @ 30°C and curve towards ~80% @ 60°.

you can also try editing the CPU Fan1 step down time.
this will control the amount of time it takes the fan to "wind down" after the temperatures change.
it could lead to the fans slowing down faster when the temp drops after closing games.
 

Armanello

Prominent
May 10, 2021
18
0
510
It seems BIOS using RPM values instead of PWM percentages. I've lowered PWM percentage to 1, 3, 5% and fan runs on about 1400 RPM. Is there a way to adjust PWM and RPM values?
 

iPeekYou

Distinguished
Jul 7, 2014
392
77
18,790
It seems BIOS using RPM values instead of PWM percentages. I've lowered PWM percentage to 1, 3, 5% and fan runs on about 1400 RPM. Is there a way to adjust PWM and RPM values?

PWM and RPM are tied to one control, since PWM dictates the percentage, as you are aware, and the RPM by the fan itself.

There's a lower limit to how slow a fan model can spin. Bigger fans can run as low as 300 RPM, a typical 120mm would probably run at 700-1000 RPM depending on model. At lower PWM percentage the fan would just spin at its minimum speed. Voltage (3-pin) controlled fans would simply stop spinning beyond its lower threshold.

Out of curiosity, is the fan fully plugged in? I had a similar issue with my GPU AIO that turns out my 4-pin connector to GPU power isn't plugged in all the way. The fans spin at 100% speed (since it's receiving 12v) due to no or bad PWM signal.

You can also try plugging in another fan to the header through a splitter or hub to see if the issue persists. Could be bad PWM chip inside Thermalright fan, unlikely, but can't hurt for deductive reasoning.
 
Solution

Armanello

Prominent
May 10, 2021
18
0
510
PWM and RPM are tied to one control, since PWM dictates the percentage, as you are aware, and the RPM by the fan itself.

There's a lower limit to how slow a fan model can spin. Bigger fans can run as low as 300 RPM, a typical 120mm would probably run at 700-1000 RPM depending on model. At lower PWM percentage the fan would just spin at its minimum speed. Voltage (3-pin) controlled fans would simply stop spinning beyond its lower threshold.

Out of curiosity, is the fan fully plugged in? I had a similar issue with my GPU AIO that turns out my 4-pin connector to GPU power isn't plugged in all the way. The fans spin at 100% speed (since it's receiving 12v) due to no or bad PWM signal.

You can also try plugging in another fan to the header through a splitter or hub to see if the issue persists. Could be bad PWM chip inside Thermalright fan, unlikely, but can't hurt for deductive reasoning.
I don't have another fan to connect and it seems fan connected properly. PWM percentage tied to RPM. But RPM values are 10x higher. Check screenshots I've made. 100% PWM equals to 15k RPM.
 

iPeekYou

Distinguished
Jul 7, 2014
392
77
18,790
I don't have another fan to connect and it seems fan connected properly. PWM percentage tied to RPM. But RPM values are 10x higher. Check screenshots I've made. 100% PWM equals to 15k RPM.
Ah alright, is that the MSI software? Could be its interfering with BIOS settings. I'm not familiar with motherboard manufacturers' desktop software, but the general gist is that they're finicky to work with and not as reliable as BIOS settings. Try uninstalling that and monitor temps/fan speed with HwInfo.
 

Armanello

Prominent
May 10, 2021
18
0
510
Ah alright, is that the MSI software? Could be its interfering with BIOS settings. I'm not familiar with motherboard manufacturers' desktop software, but the general gist is that they're finicky to work with and not as reliable as BIOS settings. Try uninstalling that and monitor temps/fan speed with HwInfo.
It's BIOS HW Monitor. I'm not using any 3rd party software.
 

Armanello

Prominent
May 10, 2021
18
0
510
It seems CPU fan is alright. It's GPU fans which are causing the trouble. I opened them, cleaned axis and it's socket, dripped a bit of machine oil before they start to wooshing. They are spinning at full RPM and never stops. HWmonitor and Gigabyte Graphic Engine shows 0 RPM. It seems sensors are broken. Does it mean I need to replace fans to make sensors work?
 
Last edited:
Fans are still loud even at 25%
may just be a design flaw in the card.
Is it possible that I damaged RPM sensors on fans? Should I replace them?
how do you think you may have damaged the fan's sensors?
why would all three of them be damaged?

if anything, i would think it is the GPU itself that couldn't properly read the fans.
in that case replacing fans would do no good.

i would doubt you could easily find 3rd party replacement fans that would correctly fit the Gigabyte cooler.
though you may find an aftermarket liquid or air cooler that could replace the Gigabyte shell.
 

Armanello

Prominent
May 10, 2021
18
0
510
I dunno for sure, but I might damaged them when opened fans. Maybe I left scratches on control boards, cause I used screwdrivers to open them.

Well, there is a plenty of fans and even heat sinks with front panel for my GPU on aliexpress. I just dunno for sure is there sensors on GPU fans?

My GPU worked pretty quietly before I cleaned it.