[SOLVED] My CPU fan suddenly makes noise for "no reason" ?

dario023

Reputable
Nov 12, 2014
6
0
4,510
As title says, my CPU fan makes suddenly a noise.. My whole configuration is with silent cooling, and CPU fan noise was maybe happening and repeating every 15-30mins and it wasn't bottering me.

Now it suddenly makes noise every 3-5 mins and it repeats again after 3-5mins, even when PC is not running any software (only google chrome opened)

My PC specifications:
GPU - ASUS RTX 2070 STRIX (tested it via msi afterburner I turned cooler speed up to 75% and it's not definetly GPU issue)
CPU: I7 9700K
CPU COOLING: Dark Rock Pro 4

MB: ASROCK Z390 EXTREME 4
Case: MSI BLACK WIDOW - Silent coolers around (and definetly when I turn on coolers, they dont make that noise)

Thermal paste should be properly set on a CPU as a "Point" or what people call "Pea" method.

I am not using thermal paste I got from cooler because I accidently lost it - I am using an cooler master paste for 6euros - 5.15v (probably should have spent more money on it, but as I was checking benchmarks, it not huge difference)

Outside of games cpu temps are going average @ 36°C (96.8 ° F) and max 54°C(129.2 ° F) - In game temps are mostly avg. 60-72°C (sometimes it can go up to 82°C)

(GPU temps are 36c - in game 68-75c max, motherboard 35c in game 45-55c)

Most imporant for me is to make your opinion about this, I am not really sure why is that noise happening when temperatures seems fine and whole configuration should be silent. PC investment wasn't small for me atm so I want it to last longer if this can cause some issue in future.
Ask me anything if it can solve this, thanks in advance for answers :D
 
Solution
Motherboards use different frequencies of PWM to control the fans. If a fan becomes off balance, or simply the size of the fan, or turbulence between multiple fans- can create a very annoying squealing sound. Try adjusting the fan profile. If this does not work..I would try another fan. I program microcontrollers all the time and if the frequency is not just right for the particular fan...there WILL be noise. I had to change a CPU fan out recently due to this exact issue.
To be honest, those temps are really good. So there's nothing to worry about.

If you're really worried about the noise, then understand that it could just be a software setting as coolers will adjust RPM depending on temperature.

An example could be that these past few days, it's been hotter, which increases room temperature by 2-3 degrees, which increases PC temps by 2-3 degrees, which could be the point where the CPU fan is configured to increase RPM in order to reduce the CPU temp.
So as long as your temps look good (which they do), you could just jump into the BIOS and manually set the cut-off points for your CPU fan.
 
Yep, the fans may buzz at particular RPMs that you rarely saw until now in the summer. Those are high quality fans with a 300,000 hour rated life so they aren't worn out, and raising their minimum speed one at a time may well prevent the noisy one from crossing the RPM where they make noise.

Or you could just try remounting the fans 90 or 180 degrees turned from where they were. Sometimes just moving them changes where they touch the heatsink enough to eliminate any noises.
 

Paperdoc

Polypheme
Ambassador
I agree this MAY be caused by some external factor like room air temp, or by a change in your own use patterns like using a more demanding game. Recognize this about fan control: the mobo automatic fan speed control system is really a TEMPERATURE control system that manipulates the fan speed to keep the temperature of the CPU (as measured by a sensor inside the CPU chip) at a target value. It tends to make changes of fan speed in steps, rather than in small continuous "tweaks" (just easier to program) so you will note the sped changes.

There is another possible cause you can check. The heatsink of that cooler system may be partially clogged with accumulated dust, reducing air flow, but that is hard to see. From the photos of this system on the beQuiet website, I see the two fans are held in place on the heatsink with silver bent springy wires at each of the four corners. It appears the fan in the middle is just slipped into the space between the two heatsink sections. Carefully see if you can rotate those spring clips to allow you to remove both fans temporarily. Then look closely through the fins of the heatsink sections - maybe you need a mirror and small light to inspect. if there does appear to be dust clogging the spaces between fins, use a vacuum or a can of compressed air to clean it out, then replace the fans.
 

dario023

Reputable
Nov 12, 2014
6
0
4,510
I agree this MAY be caused by some external factor like room air temp, or by a change in your own use patterns like using a more demanding game. Recognize this about fan control: the mobo automatic fan speed control system is really a TEMPERATURE control system that manipulates the fan speed to keep the temperature of the CPU (as measured by a sensor inside the CPU chip) at a target value. It tends to make changes of fan speed in steps, rather than in small continuous "tweaks" (just easier to program) so you will note the sped changes.

There is another possible cause you can check. The heatsink of that cooler system may be partially clogged with accumulated dust, reducing air flow, but that is hard to see. From the photos of this system on the beQuiet website, I see the two fans are held in place on the heatsink with silver bent springy wires at each of the four corners. It appears the fan in the middle is just slipped into the space between the two heatsink sections. Carefully see if you can rotate those spring clips to allow you to remove both fans temporarily. Then look closely through the fins of the heatsink sections - maybe you need a mirror and small light to inspect. if there does appear to be dust clogging the spaces between fins, use a vacuum or a can of compressed air to clean it out, then replace the fans.
PC is two weeks old, so I dont think dust can cause this in only two weeks.

Btw. Thank you guys for answers, more opinions are welcome as well. <3
 
Aug 20, 2019
3
0
10
Motherboards use different frequencies of PWM to control the fans. If a fan becomes off balance, or simply the size of the fan, or turbulence between multiple fans- can create a very annoying squealing sound. Try adjusting the fan profile. If this does not work..I would try another fan. I program microcontrollers all the time and if the frequency is not just right for the particular fan...there WILL be noise. I had to change a CPU fan out recently due to this exact issue.
 
Solution