Guide: How to set up a fan curve in the BIOS

citay

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Setting up a fan curve involves a balance between airflow and noise. But it is not that difficult when you know a good way to do it, and you only have to do it once.

First, a word about the fans. I'll try not to make it too difficult, there is just some precise terminology i have to use, but in the end it's not that hard to understand, i promise.

If you want to skip this part and go right to the information about setting up fan curves, scroll down to FAN CURVES.


There are two different types of fans, which you can tell apart by their plug. Let's look at this picture:

noctua_pin_configuration_12v_fans.png


A three-pin plug means the fan is DC (= direct current) voltage-controlled. A 4-pin plug means it's PWM (pulse width modulation) controlled.
With a DC-controlled fan, the fan speed is regulated by the board powering it with lower or higher voltages (say, between 3V and 12V) instead of steady 12V.
With a PWM-controlled fan, the board powers it with a steady 12V, and the fan speed is controlled through the fourth pin via a PWM signal.

Note: The "RPM Speed Signal" pin (rotations per minute) in the picture is telling the motherboard at which speed the fan is spinning, it is not controlling the fan.

So for each fan, you have to select the right fan control method: DC for a 3-pin fan or PWM for a 4-pin fan.


Beware: Some cheaper motherboard models may only allow DC control for most of the fan headers, or only allow PWM control for all of the fan headers, regardless of the fan headers all being 4-pin headers or not. This may save them a few cents/pennies on components around the fan headers, but it can be very inconvenient if you have the wrong type of fans, and you can't control them properly. So pay extra attention to that.

It's easy to notice in the BIOS: When you can't control some 4-pin fan headers with a PWM signal and instead only have DC (voltage) control available. Or when you don't have the ability to set a DC voltage for the fans, and you can only set a PWM percentage (then, when using 3-pin fans, they would always run at full speed here, because they would get constant 12V).

But you can also find out about this in the manual, before purchasing such a board.
Two examples of such boards. First, a board where they saved money on two of the headers:

PWM DC.png


Both CPUFAN headers can control the fan speed via PWM signal or DC voltage (depending on the fan and which control method you select in the BIOS).
But the SYSFAN headers at the bottom can only control the fan speed via DC voltage, despite having a 4-pin fan header.
"NC" means Not Connected, so they didn't implement PWM control on those headers for cost-saving. On more expensive board models, all the fan headers should be able to control fans with both methods. But in this example, you'd want your 4-pin PWM fans on the two CPUFAN headers, if possible.

Second example, from the MSI PRO Z790-S WIFI, the worst Intel Z-series board on the market:

Screenshot 2024-12-31 at 12-55-46 PROZ790-SWIFI.pdf.png


This board simply doesn't offer DC Voltage control for any fan headers, only PWM control. So if you use 3-pin case fans (or CPU fans) on this board, since they don't have the fourth wire for the PWM speed control signal, they're stuck at a full 12V. There is no way to control 3-pin fans on this board at all, the fan curves will be useless for them. You need some kind of solution like a seperate fan controller, which some cases may offer.

These shortcomings are mostly on lower-end board models. Once you go for a slightly nicer board model (from lower mid-range onwards), they should be able to have all fan headers controlled in both ways, DC voltage or PWM.


By the way: Every PWM fan can also be DC-controlled, it's just a slightly worse method of controlling it. One advantage of PWM control is that the fan will always turn on, even at a very low setting (unless it's purposely configured to stay off below 5% or 20% PWM signal for example). But when you go too low with the voltage on DC control, the fan might not turn on reliably, as the voltage is not enough to overcome the fan motor's resistance, so you'd have to add a bit of extra margin on the voltage.

The general target for the fan curves is:
- Nice low RPM (fan speed) at low temperatures
- Let the RPM ramp up gently with rising temperatures
- Only ramping up the RPM faster when the temperature approaches a quite high level.


Now, before setting the fan curves: Since we're doing this in the BIOS, this is a good time to first update the BIOS to the newest version. Because if you decide to update the BIOS later, it will reset all settings (on a lot of boards, that includes the fan curves), and you have to enter everything again. But since we'll start from scratch now anyway, updating the BIOS beforehand is a good idea.

A quick how-to on BIOS updates:
1) Get the latest BIOS. It's always the topmost one when you click on "BIOS" on the MSI support page for the mainboard.
2) Extract the file and you will get a text file and the BIOS file. Put the BIOS file into the root folder of a USB stick/drive.
3) Enter the BIOS by pressing DEL during boot, go to "M-FLASH" in the BIOS.
4) Once M-Flash (the updater) is loaded, it will show a list of your drives. Select the USB stick and select the previously extracted BIOS file on there.
5) It will ask for confirmation and then update the BIOS. It's fully automatic from there, takes about two minutes.


Now, before we come to the topic of how to set good fan curves, let's first look at a proper way to create an airflow through the case. Normally there should be at least one intake fan (usually at the front) and at least one exhaust fan (usually at the rear, in line with the CPU cooler). This will ensure a defined airflow through the case which can extract the heat from the components.

All the fans should work in unison within that airflow, to get one stream of cold air coming in from the front, picking up some heat (mostly from the CPU and GPU), and the warmed-up air being exhausted out of the rear. So in modern cases, the airflow usually looks something like this:

airflow.png
master.png



Perhaps minus the fans on top of the case. But there often will be at least one fan (if not two or three) in the front, and one exhaust fan in the rear behind the CPU cooler. Each fan will have one or two arrow markings on one of the sides, showing the rotational direction as well as the airflow direction, and all the "airflow arrows" should be pointing towards the rear of the case. When the fans come pre-installed in the case, they will already be installed like that.

If the front intake fans outnumber the rear exhaust fan by 2:1 or 3:1, then the rear fan ideally runs on slightly higher RPM than the front fans, to create a more even airflow.



FAN CURVES

Now it's time to set the fan curves. Enter the BIOS (press DEL after power-on/reboot) and open the "Hardware Monitor" which offers the fan control.
For each fan, you can set four points of a curve, MSI calls this the "Smart Fan Mode".

This is how it might look:

MSI_SnapShot_21 Fan1.png


Note that each of the four points of a fan curve is restricted by the points next to it, it can't go lower than the previous point or higher than the following point.
So you may have to move a neighboring point if you hit a restriction on the point you want to adjust.


The goal for the first point of the curve is to find a setting with a bit of airflow, but where the fan is very quiet. This will be the setting when the CPU is doing nothing (idle).
You don't need a lot of airflow when the CPU temperature is low anyway. My fans spin only at around 400 RPM there, as you can see, just enough to keep some air moving through the case. Note that i have a high-end air cooler with two fans on there, as well as three 140mm case fans in a large case. So in a small case with fewer fans, you will need a bit higher RPM to keep it this cool inside. But there is no need to have the fans spin for example at 1000 RPM in idle.

For testing, it's good to open the case and put your hand behind the fan or behind the cooler (where the air gets blown through) to feel how much airflow the fan generates with different values. As long as you don't touch the motherboard or other components, there's no danger. And you can immediately feel the results of your adjustments.

For testing the airflow, turn off "Smart Fan Mode" for a while, so you can influence the fan speed directly. You can also turn off the other fans, so you can find the sweet spot for low temperatures with the particular fan you're checking. Remember, you only need a slight airflow for this starting point of the fan curve, the goal is not to have unnecessary noise when the temperature is low.

For this goal (a bit of airflow, but being very quiet), the resulting PWM % value (or DC voltage on 3-pin fans) is your starting point at 30°C or 40°C for this fan's curve. The temperature you select depends on where you want the fan to first start ramping up. It makes no sense to define a temperature below the ambient temperature, or below the minimum CPU temperature, you'd just be wasting the whole adjustment point. So anything below 30°C only makes sense with powerful cooling methods that can actually hold the CPU below 30°C.

Next, don't go to the second point, but the third one. Find a good level where the airflow is strong but the noise is still bearable, and use this as your "full CPU load" setting for higher temperature values like 65°C or 75°C. To fine-tune this point of the curve, you might have to go back and forth from the BIOS to Windows, where you monitor the fan speed with certain CPU load and fine-tune the setting afterwards. But it doesn't take that long to do, and you only have to do it once.

As for the second point of the curve, the inbetween point: Set it slightly below a straight line between the first and third point, to not make the fans ramp up too fast at medium temperatures.

For the final point, set it for 85°C or 90°C CPU temperature and 100% PWM value (or full 12V DC with a 3-pin fan). This is the "worst case" point for safety.
Now you should have all four points of the curve set to a sensible value, and most of the time, the fan should stay between the first and the third point. The highest last point is just a safety measure.

I would always create such an "ascending dominant" curve:

curve.png


A perfectly straight line makes no sense, you'd be wasting the two middle adjustment points.
A descending dominant curve makes no sense, as it will make more noise than necessary.

Here are examples. You might of course have to use different values, but just to see how it should rougly look like. The curve needs to be done for your particular fans.

This is for a PWM fan (4-pin), which is controlled by a PWM % signal:

BIOS_Fan1.png


I would always prefer "Temperature source" CPU for the CPU fan(s), and probably most other fans too.
Usually, the CPU temperature is the most important one, and will influence the other temperatures.
Step down time 1.0s makes the fans spin down less audibly.

However, it's also feasible use "Temperature source" System for case fans. Here's an example for a DC (voltage-controlled) 3-pin fan.
Note: The following picture is not how it should be set when using the CPU temperature as the source (which is the usual temperature source),
it's an example of a fan curve when using the System temperature as the source, which could be done for case fans.
When using CPU temperature as the source, the fan curve should not be this steep, it should be more like the pictures above.

MSI_SnapShot_24 Fan4.png


Of the five total fans in my PC (two on the CPU cooler, three in the case), this lower front intake fan is the only one for which i use the "System" Temperature Source. I want it to react to the system temperature with a steeper curve, since the system temperature will obviously increase much more slowly than the CPU temperature. The graphics card can be a major contributor to heating up the whole system, and since i can't use a graphics card sensor as the temperature source, this is sort of a roundabout way to handle that. Of course, you can also have the CPU as the temperature source for all the fans, then you should use a shallower curve like in the pictures before this one.

Here's a 4-pin system fan (in my case, a Noctua NF-A14 PWM) with the CPU as the temperature source:

23 Fan3 BIOS 1.D0 MSI_SnapShot_23.png


In my system, the CPU temperature actually stays very low under load, since i have a mid-range CPU and a high-end CPU cooler. Therefore, even for the system/case fans, i can set this steep of a fan curve and not worry about getting jet engine noises under load, it will still stay pretty quiet. Depending on the individual configuration, it might be better to have the system fans on less steep of a curve compared to the CPU fan(s), just so the noise is less annoying under load. It all depends on your setup, what kind of fans you have, and noise/temperature preference.

When you have a graphics card (GPU) with a pretty high power draw, and/or there will be a lot of gaming done on the PC, then it's also a good idea to observe the various temperatures during a stint of gaming, running HWinfo Sensors in the background, set up as mentioned in step 1) of this guide with the sensors expanded. Because apart from the CPU temperatures, the GPU and other temperatures (SSD, RAM, System...) are of course also important. A GPU can take quite high temperatures, and for some cards it's not unusual or concerning to see high 80°C there under load, that can be pretty normal. But it shouldn't cause excessive temperatures for other parts. So while thinking about achieving a good balance of temperatures vs. noise, it's good to keep the entire system in mind, for example in a gaming scenario, and not only test full CPU load.


Each fan model has a different RPM range and therefore needs different values or voltages to reach a certain airflow. Also, each different PWM-controlled fan model can interpret the PWM signal differently. This is because some mainboards don't allow a PWM signal lower than 20% for example, to never have the fan turn off. So to circumvent that, a fan maker might decide to let the fan interpret a 20% PWM signal from the mainboard as "still turned off", and turn on at 21% PWM. Another fan might interpret 0% PWM as the turn off signal and 1% as the lowest possible RPM, or may never turn off and just map the entire PWM signal range to the lowest and highest RPM. And all variations in between.

Here's an example of an Arctic fan which has implemented a semi-passive mode, it stays off with any PWM signal below 5%:

P12-PWM-PST-Argb-0dB-Mode-EN.jpg


These Arctic P12/P14 PWM PST are very good fans by the way, almost unbeatable in price/performance.

Another example of a fan with a semi-passive mode is this Noiseblocker one, which has the following PWM-signal-to-fan-speed mapping (depending on the variant):

Screenshot 2023-06-27 at 21-58-11 TData_eloopX120_de_en.cdr - TData_eloopX120_de_en.pdf.png


So for each fan model, you will need different PWM values (and for 3-pin ones, different voltages), but just go by airflow and noise.
And the concept of the fan curve is always the same.

Once you're done, it's a good idea to write down your settings or make a screenshot/picture of them (in the BIOS, F12 saves a screenshot to a FAT32-formatted USB drive).
Because whenever the BIOS settings are reset (due to BIOS update, CMOS Clear or empty battery), you'll need your notes or pictures to know what fan curves you had before.
Although in BIOS updates for newer boards, the fan curves are actually kept between updates nowadays, which is good.

My other guides:
RAM explained: Why two modules are better than four / single- vs. dual-rank / stability testing

Guide: How to set good power limits in the BIOS and reduce the CPU power draw
Guide: How to find a good PSU

Someone asked me if they can thank me for my work by sending me something via Paypal: Yes, that's possible, just write me a message and i'll tell you my Paypal 😉
 
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Hey there again and (soon to be) merry Christmas o/


Apologies for taking so long with the fans, they did arrived around 2 weeks ago but one of my shoulders was so sore I couldn't lift heavy things so I had to wait xD

I've finally changed them today,
I had to use one of them in the Pump connector since fan 5 pins were at the bottom of the mobo and the cable didn't reached that far, so I hope it's alright.


Here the 3 fans settings so far,
System 1 is the 1200 rpm rear fan,

System 6 and Pump are the 1800 rpm fans you suggested me to get.

20241224_144601.jpg

20241224_144532.jpg

20241224_144524.jpg


Btw when I've reconnect the PC it took it few mins to load up, just like how it happens when I change bios settings but I didn't changed anything and old settings were kept as is, and the mobo battery is far from being dead so I hope it wasn't some bad sign...
 
Hey there again and (soon to be) merry Christmas o/


Apologies for taking so long with the fans, they did arrived around 2 weeks ago but one of my shoulders was so sore I couldn't lift heavy things so I had to wait xD

I've finally changed them today,
I had to use one of them in the Pump connector since fan 5 pins were at the bottom of the mobo and the cable didn't reached that far, so I hope it's alright.


Here the 3 fans settings so far,
System 1 is the 1200 rpm rear fan,

System 6 and Pump are the 1800 rpm fans you suggested me to get.

View attachment 196998
View attachment 196999
View attachment 197000

Btw when I've reconnect the PC it took it few mins to load up, just like how it happens when I change bios settings but I didn't changed anything and old settings were kept as is, and the mobo battery is far from being dead so I hope it wasn't some bad sign...
Hi,
bios settings for Pump on my motherboard header is unchecked cause the AIO only has one plug and a fan adpater built into it, the cpu_fan 1 motherboard header works fine for controlling the fans however your pictures included along this photo thread page by page kinda just said you plug in system rpms and temperatures for pwm and rpms and voltages for DC, however if i dont know how many volts the board is giving off and yours said 12v i dont think mine said that in bios (most likely said 10mv not 12v) could i be messing up my motherboard if i followed a curve on the pumps fans and or a system intake fan on my case *5 total intakes 2 140s pwm at 1500 rpms and 3 dc 120s at 1200rpms cause the bios defaults its 100 percent around there on capacity, ive understood the setting of smart fan control pwm and dc settings, just want a basic setup for quiet mode and extreme gaming mode. thank you bye.
 
I've finally changed them today,

Well, good, now set System Fan 6 to PWM control too, and enable Smart Fan Mode for all of them, with a decent fan curve.


however your pictures included along this photo thread page by page kinda just said you plug in system rpms and temperatures for pwm and rpms and voltages for DC, however if i dont know how many volts the board is giving off and yours said 12v i dont think mine said that in bios (most likely said 10mv not 12v)

I think you mean me, not the post above you that you quoted.

Yes, for 4-pin PWM fans, you set PWM control which is a value in percent. For 3-pin voltage-controlled fans, you set DC control. The PWM fans always get a constant 12V, their speed is fully controlled via the PWM percent value. The DC fans get a varying voltage, the minimum voltage to start spinning might be roughly around 3-5V for some fans, and with 12V they have their maximum speed. Your board will take the 12V straight from your PSU, and for the 3-pin fans, it can adjust it freely between 0-12V.

ive understood the setting of smart fan control pwm and dc settings, just want a basic setup for quiet mode and extreme gaming mode. thank you bye.

If you understood them, you have all the tools you need. You don't really need different fan curves for different circumstances, because the fan curve can take care of everything. Set very low RPM for idle / low load, so you have a quiet system. Aim for 500 RPM or so when the CPU temperature is low enough. Then for mid-temperatures you have the fan speeds slightly higher, but still below 1000 RPM. Then only for really high temperatures, you crank up the speed more.

Of course, the fan curves cannot solve everything. For example, if your cooler cannot cope with your CPU's heat output and you run into thermal throttling (high 90°C), then you either have to get a better cooler, or you have to set power limits in the BIOS according to step 1) in this guide. Meaning, you can only compensate with fan curves to some degree. If they are pretty well set up already and you still have some grave shortcoming, like way too much noise under load to keep the temperatures halfway acceptable, then sometimes you just have to upgrade/improve your cooling/airflow, more than can be done with fan curves.

The best way would be how i did it: Getting a mid-range CPU model which doesn't have an insanely high power draw, and pairing it with an overkill CPU cooler. So, right now, i have an Intel Core i5-13500 paired with a Noctua NH-D15, and the result is, this cooler can so easily deal with the CPU's heat that it doesn't have to spin its fans very fast, and the case fans also don't spin too fast. Yes, i still have my fan curve for the two CPU fans set to 100% PWM signal at 90°C, but the CPU barely gets above 60°C warm under full load. So nothing ever gets to the highest point of the fan curve.

I give general recommendations in the first post from which everyone should be able to make good fan curves for their own specific system. Once you understood the concept, it should not be that difficult, i hope.
 
Well, good, now set System Fan 6 to PWM control too, and enable Smart Fan Mode for all of them, with a decent fan curve.
That was the part I needed your help with xD
I probably shouldn't just set them like the CPU's so I need some directions,

Also should we mess with the rear fan too?
 
I probably shouldn't just set them like the CPU's so I need some directions,

I would set the curve's shape similar to the CPU fans (something like you see in my first post), but either overall at a lower level than the CPU fans. Or maybe have the first/left point of the curve at a similar setting (to achieve 400-500 RPM in idle), and then only the other three points at a lower level than those for the CPU fans. Of course, don't set it 40% lower than the CPU fans or something, try with 10% lower or so. Heck, you could even just copy the fan curve of the CPU fans for a test, see how loud it even gets. The idea is, you're gonna hear the case fans more than the CPU fans, and the CPU fans also work directly at the heat source, so they can work a little harder. But it really depends on each individual situation what is best, and this i cannot really tell without sitting in front of the system. So you're gonna have to trust your judgement a bit there, because you are in the best position to determine this. If the case fans are pretty quiet even under load, then sure, why not let them ramp up the same as the CPU fans.

If you have more intake than exhaust fans, then the exhaust fan should be on a slightly higher level for each point of the fan curve. If you have intake/exhaust ratio 1:1, they can all be on a similar curve, and if you have more exhaust than intake fans (not that common), then the intake fan(s) will have to run on a slightly higher level to even things out.
 
Alright so...
I've set my two top fans the same way as the CPU for now (have yet to test them under stressful times but so far no issues)

But came across something really werid,
I've tried to do it for me rear fan too as it was spinning in 1200 rpm all the time and I though it be no biggy to at least give it a try, but just as I was in the middle of changing things without even finish setting things up, it moved to 1800 rpm (and from what I recall, it was a 1200 rpm Noctua fan...), and stayed on that even as I've finished setting it up,

Then after a restart, It just stopped working at all, and I went back into the bios and set it back to default, and it still didn't budged,
My two though lines then were about trying to reset the electricity by turning the PC Off and completely and the other was that this fan might wasn't even a PWM type and that I've burned it from a sudden overflow of electricity,
Lucky it seem that restart the power solved it... though it does some weird noise that reminds of me of an HDD that is under stress few times at startup now and then stops...

Could it be that I really broke it to some degrees?
Also if it isn't a PWM fans wasn't the bios supposed to detect it and not give me the option to change it from DC to PWM?

I should probably check what type this fan is but I don't think I own the box anymore...
 
You can check on the cable/plug which type it is. 3-pin plug -> DC, 4-pin plug -> PWM. In DC mode, you can set the voltage so low that the fan cannot reliably turn on from a cold start, because the voltage is too low for the fan motor to overcome the initial friction. Then you can get a clicking sound and the fan might be twitching as it's struggling to get moving. In PWM control this shouldn't happen, as PWM control just supplies a steady 12V. The fans are all rated for 12V, so nothing can be damaged from this. But a DC-controlled 3-pin fan would not be reached by the PWM signal, so with PWM control it would just run at full speed since it gets the full 12V all the time.
 
You can check on the cable/plug which type it is. 3-pin plug -> DC, 4-pin plug -> PWM. In DC mode, you can set the voltage so low that the fan cannot reliably turn on from a cold start, because the voltage is too low for the fan motor to overcome the initial friction. Then you can get a clicking sound and the fan might be twitching as it's struggling to get moving. In PWM control this shouldn't happen, as PWM control just supplies a steady 12V. The fans are all rated for 12V, so nothing can be damaged from this. But a DC-controlled 3-pin fan would not be reached by the PWM signal, so with PWM control it would just run at full speed since it gets the full 12V all the time.
I see,

I've managed to find what fan it was from my order history
Seems like it's Noctua NF-A12x15 FLX 12cm 1850RPM, and seems like it's a 3 pin fan which have 3 speed settings (not sure how you change them... probably via volt as you said? it did came with different cables too for that I assume),
The fan seem to go back to normal now so I hope I didn't damage it when I've changed it to PWM for few mins, but from what you said I probably didn't....

Any idea how I can mess with its "3 speed settings" though?
 
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Those are not really speed settings on that Noctua, that's the RPM you get when using their low noise adapters, which are little adapter cables that simply result in a lower voltage than 12V. For example one adapter cable might result in 9V and the other in 7V. When you have full fan control available in the BIOS, where you can freely set fan curves between 0-12V for 3-pin fans, then obviously you don't need such adapter cables. You just use DC control and then you set a fan curve using voltages.

And no, you cannot damage any fan in any way, no matter what you set in the fan curves. The fan adjustment range is 0-12V or 0-100% PWM signal, and all normal case fans are rated for 12V. The 3-pin fans would not receive any PWM signal of course, since they lack the fourth wire. But steady 12V doesn't hurt them in any way, they just spin at their full rated RPM.

Usually, when you were to buy a new fan, and you knew that your board is capable of PWM control on enough of the fan headers, you'd always get a 4-pin PWM-controlled fan, because that method is the superior way of controlling them. Obviously there are many good 3-pin voltage-controlled fan models as well. But there you have to experiment a bit more with the lowest voltage that they will reliable turn on from on a cold boot (to have low RPM in idle).
 
I see, as always thanks for letting me know all of that.

So far my upper fans which use same curve setting as the CPU, seem to spin on around 500 rpm, at least in the last time I've checked in the bios, and they also not making any noise though even when I've stress the PC with games I was yet to reach to a point things heat up too much,

And as I've said, my rear (apparently 1850 rpm) fan spin at 1200 rpm with no obvious noise,
Would you say these settings seems alright for now (consider you suggested getting rid of the rear fan at all xD)?
 
Well, if the temperatures stay ok and it doesn't get noisy under load, that's what you want, pretty much. For the fan speeds, i would say, 500 RPM on intake vs. 1200 RPM exhaust is a pretty large difference, but it depends on your individual setup:

If you have more intake than exhaust fans, then the exhaust fan should be on a slightly higher level for each point of the fan curve. If you have intake/exhaust ratio 1:1, they can all be on a similar curve, and if you have more exhaust than intake fans (not that common), then the intake fan(s) will have to run on a slightly higher level to even things out.
 
Well, if the temperatures stay ok and it doesn't get noisy under load, that's what you want, pretty much. For the fan speeds, i would say, 500 RPM on intake vs. 1200 RPM exhaust is a pretty large difference, but it depends on your individual setup:
Looking at it again, the two top fans are on around 630 to 670 rpm (numbers always changing around these values, but for some reason one fan is more closer to the 650-670, while the other is at 630-650... could it be since the pump connector gives more electricity?),

In term of intake vs exhaust, my only intake fans are the two front fans and the big side fan which probably don't have full rpm control aside that speed button,

So two 650+- top fans vs 1200 rear fan that do the exhaustion, vs 3 fans that their speed value is unknown.
 
If you don't know their RPM, you will have to play it by ear to some extent. Apply the principles to your individual system as best you can, within the constraints that it has, and at a certain point you're done, unless you want to get a more modern case.
 
The fans can be replaced without change the case, but so far they works so I don't think I will change them anytime soon

I did some tests and got to say, these new fans aren't that quiet as I thought they be from arctic site,
Testing it in games like Red Dead Redemption 2 make them reach the 700 to 800+ RPM, however around the 750 they tend to do annoying noise which being reduced as they moved to the 800 RPM (there's still noise but more of what I'm to use to hear from fans like when they aren't stressed but about to be... dk how to describe it better)
Pics from when in RDR2:
fdsfsd.png

gdrfgdfgdfg 2.png

They can reach to 900+ a lot of times while on RDR2 as well,

On some other game which supposed to be less demending (yet still somewhat heavy I guess, just not RDR2)
They reached to the 1000 too
2024-12-29 080808.png

2024-12-29 081454.png

From my tests so far, the noise seem to start from around 700 RPM but the most annoying point is around the 700 to 750,
At 800 you can hear the fans speed up but they don't make an annoying noise, and at 650- you barely hear them,
My former fans (At least one of them which I could monitor) were always around the 600 to 650 or maybe even 700 RPM, so I guess I never reached the point where it start making that annoying noise though it's also depends on the fan type,

My rear fan is at 1200+ RPM and I can bearly hear it on the other hand,
I've kinda assumed their fans will be less noisy but maybe my expectations were too high,

What also kinda bothers me is that the top fans seem to be at least 200 RPMs above the CPU's fan, and that from the two top fans one always seems to be on around 50+- higher RPM than the other, is that normal/good?
 
From my tests so far, the noise seem to start from around 700 RPM but the most annoying point is around the 700 to 750,
At 800 you can hear the fans speed up but they don't make an annoying noise, and at 650- you barely hear them,

Yes, sometimes you can have certain RPM ranges where, due to air turbulence from whatever obstacle is right in the front of the fan for example, there can be some annoying noise. Then you have to adjust the fan curves accordingly, so that the fans don't remain in that RPM range. Just set the two middle fan curves a bit lower (or higher), until you can make them avoid this range. Either stay below it for mid-temperatures, or go above it.

and that from the two top fans one always seems to be on around 50+- higher RPM than the other, is that normal/good?

Again, it can depend on their position and what's right in front of them. But also, how the airflow works inside of the case. Maybe one fan is hit more with direct airflow and thus its motor has to do less work and spins a bit faster, while the other motor has to do all the work itself. And of course there can be normal tolerances from the factory, you're never gonna have two fans have the very same RPM, not even my Noctua fans are like that (although they have tight tolerances).

If they're completely different fan models, then yeah, of course the RPM are gonna be different, each fan reacts differently to a certain PWM percentage or voltage. That's why you would then go more by the RPM, the airflow and the noise. For example, when i set a fan curve for a new case with fans i don't know (how they behave), i will take off the side panel and play with the fan settings while holding my hand into the case, where the fans are blowing the air to. Heck, if you wanted to "see" the airflow, you could even hold an incense stick in front of the air intakes or something like that, so you see where the smoke moves.

The idea is to get a pretty even airflow front to rear, or front to top/rear, maybe with a slight overpressure (slightly more intake than exhaust airflow). And have it all nicely balanced with temperatures vs. noise. Anything you don't like, you have to experiment and try to change, until you find a decent compromise of all the factors.
 
I see,
Here is the curve so far, by middle you mean mostly messing with the 30c to 50c dots?
20241229_194914.jpg


As for different fan conditions and types, while the CPU fan is obviously different from the two upper fans, and definitely somewhat blocked by the heatsink,
Does it still recommended to keep it or the upper top fans at 200 rpm different from each other? or should I adjust one of them like the top fans so they will slow down a bit to be closer to the CPU's even if the temp is the same?
Consider I don't hear them much at 600-650 rpm, and that the CPU fan also at 600 rpm most of the times, won't it be better?

 Though the upper fans got their own job taking out the hot air so maybe they do need to be faster than the CPU's, but as I'm uncertain in it considered I'm no expert in these kind stuff I rather wait for your answer (sorry if I'm making something obvious sound more harder than it should be xD).
 
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Those are not really speed settings on that Noctua, that's the RPM you get when using their low noise adapters, which are little adapter cables that simply result in a lower voltage than 12V. For example one adapter cable might result in 9V and the other in 7V. When you have full fan control available in the BIOS, where you can freely set fan curves between 0-12V for 3-pin fans, then obviously you don't need such adapter cables. You just use DC control and then you set a fan curve using voltages.

And no, you cannot damage any fan in any way, no matter what you set in the fan curves. The fan adjustment range is 0-12V or 0-100% PWM signal, and all normal case fans are rated for 12V. The 3-pin fans would not receive any PWM signal of course, since they lack the fourth wire. But steady 12V doesn't hurt them in any way, they just spin at their full rated RPM.

Usually, when you were to buy a new fan, and you knew that your board is capable of PWM control on enough of the fan headers, you'd always get a 4-pin PWM-controlled fan, because that method is the superior way of controlling them. Obviously there are many good 3-pin voltage-controlled fan models as well. But there you have to experiment a bit more with the lowest voltage that they will reliable turn on from on a cold boot (to have low RPM in idle).
3-pin set that came with my case at 1200 rpms bios curved dc running in the smart fan mode curve selector it does not give VOLTS just a system fan temp and rpm % with no volt in bios hardware monitor, cause they have intake setup i would want to know why my bios does not connect to the motherboard by volts and *10mv is the standard on it which means nothing to me right? I just get the basics of bios fan control on intake fans running lower than aio top mounted fans exhausted to push neutrally but the dc system does function on its curve of two bottom pwm fans and three dc front intake fans.
 
I see,
Here is the curve so far, by middle you mean mostly messing with the 30c to 50c dots?
View attachment 197174

As for different fan conditions and types, while the CPU fan is obviously different from the two upper fans, and definitely somewhat blocked by the heatsink,
Does it still recommended to keep it or the upper top fans at 200 rpm different from each other? or should I adjust one of them like the top fans so they will slow down a bit to be closer to the CPU's even if the temp is the same?
Consider I don't hear them much at 600-650 rpm, and that the CPU fan also at 600 rpm most of the times, won't it be better?

 Though the upper fans got their own job taking out the hot air so maybe they do need to be faster than the CPU's, but as I'm uncertain in it considered I'm no expert in these kind stuff I rather wait for your answer (sorry if I'm making something obvious sound more harder than it should be xD).
how is it that i dont see a pump option for my computer bios ? i understand the point of connection via i dont have a connection for my aio production year, it only has a cpufan plug so i cant not do that part right?
 
Well, good, now set System Fan 6 to PWM control too, and enable Smart Fan Mode for all of them, with a decent fan curve.


point one is at 500rpm for system fans intake and exhuast for idle, point two is mid level temps at 1000rpm for intake and exhaust, what are these temperatures for bios editing? also might as well throw out a 100% temp cap too, my next question is what is a good dot to add for the fourth in between temp and fan% ? All are going to be entered in the same smart fan control above, to test on gaming, with bios operation only and hw Monitor for a little test on coolant temp running fast game needs.

I think you mean me, not the post above you that you quoted.

Yes, for 4-pin PWM fans, you set PWM control which is a value in percent. For 3-pin voltage-controlled fans, you set DC control. The PWM fans always get a constant 12V, their speed is fully controlled via the PWM percent value. The DC fans get a varying voltage, the minimum voltage to start spinning might be roughly around 3-5V for some fans, and with 12V they have their maximum speed. Your board will take the 12V straight from your PSU, and for the 3-pin fans, it can adjust it freely between 0-12V.



If you understood them, you have all the tools you need. You don't really need different fan curves for different circumstances, because the fan curve can take care of everything. Set very low RPM for idle / low load, so you have a quiet system. Aim for 500 RPM or so when the CPU temperature is low enough. Then for mid-temperatures you have the fan speeds slightly higher, but still below 1000 RPM. Then only for really high temperatures, you crank up the speed more.

Of course, the fan curves cannot solve everything. For example, if your cooler cannot cope with your CPU's heat output and you run into thermal throttling (high 90°C), then you either have to get a better cooler, or you have to set power limits in the BIOS according to step 1) in this guide. Meaning, you can only compensate with fan curves to some degree. If they are pretty well set up already and you still have some grave shortcoming, like way too much noise under load to keep the temperatures halfway acceptable, then sometimes you just have to upgrade/improve your cooling/airflow, more than can be done with fan curves.

The best way would be how i did it: Getting a mid-range CPU model which doesn't have an insanely high power draw, and pairing it with an overkill CPU cooler. So, right now, i have an Intel Core i5-13500 paired with a Noctua NH-D15, and the result is, this cooler can so easily deal with the CPU's heat that it doesn't have to spin its fans very fast, and the case fans also don't spin too fast. Yes, i still have my fan curve for the two CPU fans set to 100% PWM signal at 90°C, but the CPU barely gets above 60°C warm under full load. So nothing ever gets to the highest point of the fan curve.

I give general recommendations in the first post from which everyone should be able to make good fan curves for their own specific system. Once you understood the concept, it should not be that difficult, i hope.
 
Well, good, now set System Fan 6 to PWM control too, and enable Smart Fan Mode for all of them, with a decent fan curve.




I think you mean me, not the post above you that you quoted.

Yes, for 4-pin PWM fans, you set PWM control which is a value in percent. For 3-pin voltage-controlled fans, you set DC control. The PWM fans always get a constant 12V, their speed is fully controlled via the PWM percent value. The DC fans get a varying voltage, the minimum voltage to start spinning might be roughly around 3-5V for some fans, and with 12V they have their maximum speed. Your board will take the 12V straight from your PSU, and for the 3-pin fans, it can adjust it freely between 0-12V.



If you understood them, you have all the tools you need. You don't really need different fan curves for different circumstances, because the fan curve can take care of everything. Set very low RPM for idle / low load, so you have a quiet system. Aim for 500 RPM or so when the CPU temperature is low enough. Then for mid-temperatures you have the fan speeds slightly higher, but still below 1000 RPM. Then only for really high temperatures, you crank up the speed more.

Of course, the fan curves cannot solve everything. For example, if your cooler cannot cope with your CPU's heat output and you run into thermal throttling (high 90°C), then you either have to get a better cooler, or you have to set power limits in the BIOS according to step 1) in this guide. Meaning, you can only compensate with fan curves to some degree. If they are pretty well set up already and you still have some grave shortcoming, like way too much noise under load to keep the temperatures halfway acceptable, then sometimes you just have to upgrade/improve your cooling/airflow, more than can be done with fan curves.

The best way would be how i did it: Getting a mid-range CPU model which doesn't have an insanely high power draw, and pairing it with an overkill CPU cooler. So, right now, i have an Intel Core i5-13500 paired with a Noctua NH-D15, and the result is, this cooler can so easily deal with the CPU's heat that it doesn't have to spin its fans very fast, and the case fans also don't spin too fast. Yes, i still have my fan curve for the two CPU fans set to 100% PWM signal at 90°C, but the CPU barely gets above 60°C warm under full load. So nothing ever gets to the highest point of the fan curve.

I give general recommendations in the first post from which everyone should be able to make good fan curves for their own specific system. Once you understood the concept, it should not be that difficult, i hope.

Hi read this if its accurate and critique =- point one is at 500rpm for system fans intake and exhuast for idle, point two is mid level temps at 1000rpm for intake and exhaust, what are these temperatures for bios editing? also might as well throw out a 100% temp cap too, my next question is what is a good dot to add for the fourth in between temp and fan% ? All are going to be entered in the same smart fan control above, to test on gaming, with bios operation only and hw Monitor for a little test on coolant temp running fast game needs.
 
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