[SOLVED] Fans going too fast after power outage

Saint Grimm

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After a power outage this morning, I turned my PC back on and the fans just started up going very fast. So fast that one of them has started making a clicking noise, and sitting at my desk is like sitting right next to a fan blowing cold air directly into my face.

I looked in my bios, the speed is set to standard. I tried changing it to other options and there was no difference. It says the PCH fan is running at 3900RPM The CPU fan is running over 2800RPM and the case fans have never shown up to tell me their speed, but they're blowing air out of my case like an industrial fan right now.

The CPU temp is at 45c and the motherboard temp at 32c when in bios.

With windows open, the fans are still spinning insanely fast and loud.

According to core temp, the temp is sitting around 60c for CPU, but has hit a max of 85c, which is very high, I normally play Assassin's Creed Valhalla at 71c. 85c is something I've NEVER seen before, 80c is the absolute highest I've ever seen it.

But 85c happened BEFORE I opened the game. Opening the game somehow made it drop in temp, which makes NO sense at all to me...

image-2022-01-21-114839.png


EDIT: Found elsewhere that updating the bios could sort out the problem if the power outage did something to the motherboard? I have to go to walmart soon, I'll try that out and report back in a couple of hours when I get home.
 
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Solution
one of the fans on the top of the case is just as loud as it was when it was going at max speed... It almost sounds like a car idling.

Is there a way to fix that?
depends on the type of fan and how it is connected.
SATA or molex powered fans run at a constant RPM.
3pin fans need to be controlled through BIOS DC mode.
4pin PWM fans can be controlled through BIOS PWM or through AI Suite's Fan Xpert.
the case has 2 fans ontop. Can I just unplug the one that's loud or is that a heat risk?
you can go ahead and try.
it can't actually hurt anything.
even if the CPU did start to overheat it will first throttle down it's core speed and if it continues to rise it would then just shutdown before any damage could occur.
but losing...

Saint Grimm

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try 'Load Optimized Defaults' in the BIOS Exit page.
if still no difference, try resetting CMOS.

if still no difference, replace the battery, but i doubt it will change anything.
if the battery were dying you would probably see other issues.

No difference after optimized defaults. No clicking and overall slower speeds after cmos reset, 2800rpm on pch fan and 2600 on cpu.

So what do I do? Just live with the fans being loud as hell? Or is this issue just going to branch out to more crap so I need to replace something?
 
is the BIOS fan control set to manual PWM control?
if so, there may be either a malfunction with the BIOS or the motherboard's fan controller.
you could try flashing the latest BIOS, or if you have already, re-flashing to the latest and see if it allows proper control.

also if your motherboard control software offers fan control you may still be able to set custom curves from inside of the OS.
or there are some 3rd party softwares out there that allow the same options.

try that and see if the software can gain control where the BIOS settings don't seem to be working.
 

Saint Grimm

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Yes, bios set to manual PMW. Flashed to latest with nothing.

Asus AI suite says my cpu fan's highest speed was 1932+12 rpm. Current speed, with buncha stuff open is only 500rpm. But in bios it claimed it was doing 2600rpm.

I can't tell by sight if the cpu is actually going faster than normal. I can't tell if the pch fan is either. But the case fans are clearly going too hard, the fan on the backside of the tower is facing my desk, and it's blowing out air harder than my pedestal fan.
 

Saint Grimm

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I double checked if the pins are in the MB or directly to the power supply, as someone on discord said it's most likely NOT the power supply if they're plugged into pins on the MB - They are.

I unplugged them, started the pc up. shut it down. plugged them back into the MB and the fans seems to be going at a much more normal speed now. However one of the fans on the top of the case is just as loud as it was when it was going at max speed... It almost sounds like a car idling.

Is there a way to fix that? When the fan isn't spinning, it doesn't sound that way, so I know for sure which specific fan is making the sound. It also didn't sound like that before all this fan business.... So is there something I can do to shut it up now? Or is that just how that fan sounds from now on?

EDIT: the case has 2 fans ontop. Can I just unplug the one that's loud or is that a heat risk? The one making the noise is the one that's above the CPU on the top, ofc couldn't be the one over the RAM or something....

This is the exact case I have, if that helps answer my question

https://www.newegg.com/p/N82E16811353100?Item=N82E16811353100
 
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one of the fans on the top of the case is just as loud as it was when it was going at max speed... It almost sounds like a car idling.

Is there a way to fix that?
depends on the type of fan and how it is connected.
SATA or molex powered fans run at a constant RPM.
3pin fans need to be controlled through BIOS DC mode.
4pin PWM fans can be controlled through BIOS PWM or through AI Suite's Fan Xpert.
the case has 2 fans ontop. Can I just unplug the one that's loud or is that a heat risk?
you can go ahead and try.
it can't actually hurt anything.
even if the CPU did start to overheat it will first throttle down it's core speed and if it continues to rise it would then just shutdown before any damage could occur.
but losing a single exhaust fan can't really alter temperatures that much anyway.
 
Solution

Saint Grimm

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Feb 25, 2014
186
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depends on the type of fan and how it is connected.
SATA or molex powered fans run at a constant RPM.
3pin fans need to be controlled through BIOS DC mode.
4pin PWM fans can be controlled through BIOS PWM or through AI Suite's Fan Xpert.

you can go ahead and try.
it can't actually hurt anything.
even if the CPU did start to overheat it will first throttle down it's core speed and if it continues to rise it would then just shutdown before any damage could occur.
but losing a single exhaust fan can't really alter temperatures that much anyway.

I thought the back fan was the only exhaust fan lol. I thought all 4 others pulled air into the PC, but if it's just an exhaust I might not even worry about replacing it unless I start noticing heat issues. Unplugged now and it's so peaceful and quiet in here once again <3, and all fans seem to be moving at appropriate speeds, thank you!
 
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