Question My CPU cooler is always at high speed even though my CPU temperature is low

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May 29, 2023
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Hi i have a i5-11400f and i use stock cooler, the problem is my CPU cooler running at more than 2800 pwm even when CPU temperature is less than 40c (some time 30c). My motherboard is prime B560M-A.
so what is the problem?
(Sorry for my English)
 

Karadjgne

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If you've tuned the fan, and still shows 2903rpm for 10% there's only 3 possibilities. Either you skipped a pin and the fan isn't actually put on all 4 pins, the fan pwm circuit is busted or the motherboard pwm circuit is busted.

Swap the closest other pwm fan with the cpu fan, just swap the wiring. Then retune. If you have some control then of the fan on the cpu (system header) and no control of the case fan (cpu fan header) you'll know its a motherboard issue. If still no control of the cpu fan (system fan header) then it's a fan issue.
 
May 29, 2023
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ok I connected both fan (10100f stock cooler and 11400f stock cooler). the motherboard has CPU_FAN and OPT_FAN.
the 10100f stock cooler work fine in both header (CPU_FAN and OPT_FAN) and it gose from 900rpm to 3000 rpm at full speed.
but
the 11400f stock cooler work the same speed (around 2800rpm and no matter what I did, it never goes lower then 2800rpm (still has some small change at rpm) I tested the cooler at both header (CPU_FAN and OPT_FAN) and still same result.
so, I think the 11400f stock cooler is defective? now if this is the case is dangerous to use this cooler for my CPU? is it possible to damage something?
 
May 29, 2023
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Are they in any way different?
Can you show a photo, to compare?
look I plugged both cooler, one to the CPU_FAN and the other one to the OPT_FAN at the same time and test the speed of each cooler then switch the cooler to the different fan header (CPU_FAN, OPT_FAN).
I all test the 11400f stock cooler stayed at above around 2800 rpm (no matter which header I connected this cooler to it still above 2800 rpm)
but the 10100f stock cooler was completely fine whether I plugged to the CPU_FAN or OPT_FAN its speed went from around 900 rpm to 3000 rpm at full speed.
(Sorry I know my English is really bad, I'm trying to be understandable as much as possible)
 
I all test the 11400f stock cooler stayed at above around 2800 rpm (no matter which header I connected this cooler to it still above 2800 rpm)
but the 10100f stock cooler was completely fine whether I plugged to the CPU_FAN or OPT_FAN its speed went from around 900 rpm to 3000 rpm at full speed.
Do those coolers look different? Visually?
11400f 10100f both have thermal design specification of 65W.
So coolers should be very similar, if not identical.
 

Karadjgne

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In most lower to mid grade motherboards cpu_fan and cpu_opt are the same, controlled in bios as cpu, there's no difference. So you saying that the one fan responds and the other just runs max means there's an issue in the fan, the pwm is broke.

No, it won't hurt at all. Think of it like a lawn tractor, you put the engine on high speed and just drive, whether that's drive slow or drive fast makes no difference, the engine just sits at high speed. If the speed is low, and you try to drive, it will stall. A cpu would overheat. So being stuck at max is no worries.

It's your choice, use either. Both should work, but you'll probably see slightly better temps at low loads with the busted fan because it's at max whereas the good fan will go up and down with the load and temp. But. I'd sacrifice that because the fan is busted and there's no guarantee it'll stay at that level, it may decide to one day be at 50% and mid game you overheat, blue screen and no idea exactly why.
 
May 29, 2023
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Do those coolers look different? Visually?
11400f 10100f both have thermal design specification of 65W.
So coolers should be very similar, if not identical.
Yes the
11400f stock cooler has 12V * .28A
and
10100f stock cooler has 12V* .18A
and of course, there is a bunch of serial number/ part number which are different in both cooler
In most lower to mid grade motherboards cpu_fan and cpu_opt are the same, controlled in bios as cpu, there's no difference. So you saying that the one fan responds and the other just runs max means there's an issue in the fan, the pwm is broke.

No, it won't hurt at all. Think of it like a lawn tractor, you put the engine on high speed and just drive, whether that's drive slow or drive fast makes no difference, the engine just sits at high speed. If the speed is low, and you try to drive, it will stall. A cpu would overheat. So being stuck at max is no worries.

It's your choice, use either. Both should work, but you'll probably see slightly better temps at low loads with the busted fan because it's at max whereas the good fan will go up and down with the load and temp. But. I'd sacrifice that because the fan is busted and there's no guarantee it'll stay at that level, it may decide to one day be at 50% and mid game you overheat, blue screen and no idea exactly why.
Yeah, using a broken fan, especially for the CPU, is not a good idea even if it works at full speed. Therefore, I use the 10100f stock cooler which is working normally.

Another thing, the 11400 stock cooler does not have a smooth surface on the heat sink which scratched my CPU's IHS. Do you think this could have any impact on my CPU (i5-11400f)? Right now the CPU temperature is CPU package: around 40 C, CPU: 38C in idle time. Is this a normal temperature?
 
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May 29, 2023
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what happens it you use silent or turbo in the cpu fan settings also did notice that your havind only 2 case fans how they are set in the case since they run at high speed also give name amd model of your case .
I’m Iranian and the case and the two case fans are made by an Iranian company. I don’t know how bad its (my case) airflow is, but one thing for sure is that the 11400f stock cooler was defective, and if that wasn’t bad enough, the heatsink surface is not smooth which causes minor scratches on the CPU’s IHS.
here is the link for my case:
and this is for my case fan: (I have two of this fan, one for right sid and one for upper side) + 1 fan with fixed rpm, 1200 for back of my case I guess
 
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scout_03

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i would put 2 of those fan in front as intake and 1 on top as exhaust with the back one leave the side one empty for now and recheck your temp if the back one could be remove get on of this gf to replace it since case have good cooling option another thing would be to get a aftermarket cooler for the cpu .
 
May 29, 2023
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room temperature is around 30c
I run CinebenchR23 (as you can see in the screenshot) for 10 minutes
do you think that the temperature in the CPU and CPU package (basically everything you see in the screenshot is ok)
the temperatures that you see in the screenshot are maxed and it didn't go higher than that at 10 min of running CinebenchR23.
and I replace the CPU cooler with a 10100f stock cooler.
View: https://imgur.com/a/c8pXoMc
View: https://imgur.com/a/kqbtIJJ

View: https://imgur.com/a/yiOR1Dz
 
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Nice Nicer

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May 24, 2021
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I think those temps are alright. A little below seventy under full load with a high ambient temperature ist quite good. It probably would go a bit higher If you let cinebench run for half an hour, but that's probably not a very realistic scenario If you don't play very CPU intensive games or do a lot of video editing or something like that. I would say, this is surprisingly good performance for a stock cooler.