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Fan curves don't work as expected?

Joined
Aug 13, 2009
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Location
Czech republic
Processor Ryzen 5800X
Motherboard Asus TUF-Gaming B550-Plus
Cooling Noctua NH-U14S
Memory 32GB G.Skill Trident Z Neo F4-3600C16D-32GTZNC
Video Card(s) Sapphire AMD Radeon RX 7900 XTX Nitro+
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Case Fractal Design Define R6 Black
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Power Supply Seasonic PRIME Ultra 650W Gold
Mouse Roccat Kone AIMO Remastered
Software Windows 10 x64
In addition to my stupid graphic card noise, I can't seem to be able to configure the system fans.
Maybe I misunderstood how the fan curves work - you tell me.
CPU fan
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case fan
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I thought the points work so that once given temperature is reached, the fan switches to higher speed as defined.

But that's not the case.
I let BF4 run in the background, but the fans are still at their lowest settings. The case fan (chassis 3) for example should spin at ~900 rpm, which is more or less the 45% I set, not 700.
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Can anyone tell me what the hell is wrong here?

Someone has just told me the board/CPU uses the CPU and not CPU package sensor for fan settings, which is bad, because that sensor reports significantly lower temperatures.
 
Did you take into account the 12second delay till it actually ramps up?
 
That's what I added later on, that's not the problem. Also I keep the game running in the background so the CPU reaches the max temperature.
 
I haven't seen boards using package temp. What's the problem tailoring the curve according to right CPU temperature?
 
I dont like BIOS fan curves so I use AfterBurner. Not sure how many 'points' there are in the average BIOS curve, but in AB I use 8.
fan curve.PNG
 
I haven't seen boards using package temp. What's the problem tailoring the curve according to right CPU temperature?
Because there is no direct relationship between the two temperatures. I don't know what to set the curve to.
Maybe you don't understand.
The motherboard reports (and shows in the BIOS obviously) two CPU temperatures: "CPU" and "CPU package". "CPU" is some bullshit. "CPU package" is the real temperature.
BUT the motherboard uses the "CPU" for FAN settings, not the real one, which makes it impossible to set the curves properly, because I have no idea what the bogus temperatures would be like.
 
45% duty cycle doesn't equal 45% of maximum RPM.
 
What is it then?
 
What is it then?
It is what it is, it's a logarithmic curve, volts in to rpm are not a linear curve I think.
Initially it won't spin at all upto 3-6v then it starts so non linear.
 
What is it then?

It is PWM signal level. Mathematically it represents a logarithmic curve. Usually x = a^y + b. It ain't very curved.

Basically just do the graph based on CPU temps and call it a day. The basis for that could be that the temp data is gathered from external LPC controller what communicates with the CPU and it does manage the fans, it is a more robust solution.

In windows you access the internal procesor data, so you get more sensor data so don't mix up things.

Just adapt... it ain't that hard.
 
What about using SpeedFan
 
It is PWM signal level. Mathematically it represents a logarithmic curve. Usually x = a^y + b. It ain't very curved.

Basically just do the graph based on CPU temps and call it a day. The basis for that could be that the temp data is gathered from external LPC controller what communicates with the CPU and it does manage the fans, it is a more robust solution.

In windows you access the internal procesor data, so you get more sensor data so don't mix up things.

Just adapt... it ain't that hard.
Why is nothing ever simple? I know nothing about math (and what I knew I forgot 20 years ago, thankfully) and my head already looks like a baloon.

When I did the grap based on CPU temps it didn't work, that's what I described in the original post. Do you not get it? I know the real temps, but I don't know the bogus temps equivalents the fan controller uses, so I can't configure it.
 
Best thing to do is to avoid using BIOS fan curves, it is annoying.

Like @DeathtoGnomes i used AfterBurner, now i am using iCUE and have it set this way: from 20c to 30c the fans runs at 800rpm, at 35c they run 900rpm, at 40c 1250rpm and 45c+ 1500rpm

Screenshot - 21_02_2021 , 14_39_20.png
 
Why is nothing ever simple? I know nothing about math (and what I knew I forgot 20 years ago, thankfully) and my head already looks like a baloon.

When I did the grap based on CPU temps it didn't work, that's what I described in the original post. Do you not get it? I know the real temps, but I don't know the bogus temps equivalents the fan controller uses, so I can't configure it.

If you are sure those are PWM fans you have there... you can experiment and switch to QFAN voltage regulated mode. Revert the delays you put there also. Use CPU-Z bench for quick lookup if it ramps up.
 
I use Asus fan expert.
I am not an expert on fan controls I normally let the bios do this automatically but now that there is this fan expert app well it's brainless set and forget lol.
Any way I really would like to know why they have 2 different CPU temp's now. This is stupid!
Why can't they just give us a fing temp reading to go by and stop all the confusion?

Best thing to do is to avoid using BIOS fan curves, it is annoying.

Like @DeathtoGnomes i used AfterBurner, now i am using iCUE and have it set this way: from 20c to 30c the fans runs at 800rpm, at 35c they run 900rpm, at 40c 1250rpm and 45c+ 1500rpm

View attachment 189305
Isn't After burner some MSI program? I thought it was like "MSI After burner" or some shit like that..
At any rate I would not use that POS APP I have been around MANY years and every time I used that POS program in the past all it did was give me a head ache. LOL.
Not saying it don't work for you all just never liked the user interface nor the way it interfaced with my system. Causing crashes and lockups.

My advice is to see if the MB you have has a built in AI suite. or some thing like it.

TPU screen.jpg
 
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I use Asus fan expert.
I am not an expert on fan controls I normally let the bios do this automatically but now that there is this fan expert app well it's brainless set and forget lol.
Any way I really would like to know why they have 2 different CPU temp's now. This is stupid!
Why can't they just give us a fing temp reading to go by and stop all the confusion?
Doesn't that do exactly the same thing as what you can do from within the BIOS?


Oh and another thing that makes all this even bigger problem that I have just noticed: the inside of the case heats up before the CPU hits any significant temperature because of the graphic card, which in turn eventually spins its fans faster than it could have.
The CPU fan itself might be okayish, but there's no good way to control the case fan. It can be based on CPU temperature, chipset, and something else, none of which really help. I can't set the lowest speed (which would help in this case) it too high because it produces really annoying noise due to pushing air through the case grille. Unfortunately there's likely no solution for this part of the problem, because the fans are completely separate.
 
Isn't After burner some MSI program? I thought it was like "MSI After burner" or some shit like that..
Yes it is.

Doesn't that do exactly the same thing as what you can do from within the BIOS?
I assume it does :rolleyes:only thing that changes is that you download it from the Asus website and install it so you dont need to go into the Bios :sleep:
 
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Doesn't that do exactly the same thing as what you can do from within the BIOS?


Oh and another thing that makes all this even bigger problem that I have just noticed: the inside of the case heats up before the CPU hits any significant temperature because of the graphic card, which in turn eventually spins its fans faster than it could have.
The CPU fan itself might be okayish, but there's no good way to control the case fan. It can be based on CPU temperature, chipset, and something else, none of which really help. I can't set the lowest speed (which would help in this case) it too high because it produces really annoying noise due to pushing air through the case grille. Unfortunately there's likely no solution for this part of the problem, because the fans are completely separate.
Yes and NO. See you have to be in the bios to in order to adjust the fans here you are in the real working environment.
It sounds like you need a better case with more air flow and a new After market ( if you do not already ) CPU cooler.
You have lots going on and you will need to start with a case first.
 
The case is perfectly fine and so is the cooler.
The airflow is directly related to the fan speed.
 
The case is perfectly fine and so is the cooler.
The airflow is directly related to the fan speed.
No not if the video card is heating up the inside of the case (as well as everything else). But Hey if you say so I am dipping out take care good luck.
 
Feel free to inspect my system specs before coming to wrong conclusions.

The physical dimensions and layout of a case don't CREATE any airflow.
 
I'm having a similar problem, did you find solution?
 
are you not able to set these curves using your motherboards fan control?
 
Stop that step up. It is hysteresis, you are setting a 3.6 second latency which kills the benefit of having minute response to temperature changes.
You might be running two overriding monitoring utilities which disrupt one another from accessing the gpu fan curve.
You might be running too wide q-fan bios fan control ranges. If the range is all the way, it controls 1000-5500rpm over the same 100% spectrum which kills variability for your hearing deficit sake. You need to go to your bios, select a narrower qfan range(like 20-40% I forgot mine) such that when windows takes over and the ranges are defined on qfan's limits, 100% does not cause deafness and 0% does not just run idle and actually move some air without being particularly loud.
Also, if you let the fans idle, the air volume will start heating and increase your case temperature until ramping the fans won't be able to effectively dissipate the air quickly. Always keep more air circulation than not.
One last item, if you want to control your gpu fan, just open up your monitoring utility, mark each percentile's rpm and form your own linear fan ramp curve. You'd be surprised how close and far each percentile gets, somewhere around 40%, the fan velocity was most divergent and the individual 10 fan curve spots got the closest there.
 
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