Question fan header being weird. Making my new fans way more loud than they should be.

Nov 17, 2020
18
0
20
1
Here is my issue. I built my own computer about a week ago. When I got it, I put in 3 extra fans for exhaust and put the 2 120mm fractal fans that came with my case as intake. The 3 exhaust fans were plugged into a splitter to the cpu fan 2 while the 2 intake fans were plugged into the the 2 fan headers on the bottom of my motherboard. The 3 extra fans that I had bought were really loud because they could spin at a high rpm. I tried to set the fan curves, but since I have an asrock board, I was limited to control my fans by percentage of the highest rpm. They were marketed as fans that could go from 1000 to a little above 2000, like 2100 or something like that. but not any more than that. When I set fan curves, you have to run a fan test. So I did and it reported back as 100% fan speed as 2666 and 10% fan speed as 1375. I figured it was the fans fault and not my motherboard, or a combination of both because I could only control by percentage. I'm going to return them. I was researching and stumbled across the arctic p12. Quiet, 120mm, $10 fans. Everyone says that they are great. So I bought them. Once they came, I swapped them out from my old fans that I thought were too loud, and plugged them back into the cpu fan 2 header since it was the only one that they could reach. Also arctic fans can be daisy changed so thats what I did. Thinking that that would fix the noise, it didn't and when I went to run another fan test to set the percentages to the rpms, and it came back with the say percentages as last time from my old fans. What do I do? Is there anyway to reset fan profiles or something? Thanks for reading all this btw. Came out to a small novel lol.
 

Paperdoc

Glorious
Ambassador
Here's a likely explanation and fix. Those Arctic fans are the older 3-pin design, and I would bet the ones you replaced also were that way. The METHOD by which the mobo header used for those fans can control their speed is different from what is used for the new 4-pin PWM fan design. Most mobos allow you to set that item for each fan header separately in BIOS Setup.

Go into BIOS Setup for the header your fans are plugged into. Look for an item where you can set to either Voltage Control Mode (aka DC Mode) or PWM Mode. Set it to Voltage Control Mode (aka DC Mode). This is the only way to control that fan type's speed. When done, Esc to the Min Menu, use F10 to get to the Exit Menu, and be sure to choose SAVE and EXIT to sace your new setting and reboot. This should let your fans run slower.
 
Nov 17, 2020
18
0
20
1
Thank you so much! that fixed it. Turns out that the issue was that I had plugged the fans into the wrong header which was meant to be for the cpu pump if I had one. That made the fans give me weird readings and spin at high rpms to begin with. Either way its fine now.
 

Paperdoc

Glorious
Ambassador
That certainly explains it. Most often the header intended for the pump of an AIO cooler system for your CPU is set up NOT to do any speed control. Most AIO pumps are designed to run at full speeed with a full 12 VDC power supply at all times, so speed control is NOT wanted there.
 
Nov 17, 2020
18
0
20
1
Yea thats what I figured. Also now my stock amd cpu cooler is giving me high rpms and won't let me go any where below 1400 rpm. Its plugged into cpu fan 1 now, a little loud but acceptable. Is there anyway that the fan header issue might have mixed up my cpu cooler? thanks
 

Paperdoc

Glorious
Ambassador
If your stock CPU cooler is plugged into the CPU_FAN header, then it should be responding to the actual temperature inside the CPU chip. That's how that header operates IF you tell it to use it normal automatic speed control strategy, often called its Profile. That item is where you can select a Normal or Default Profile, or a fixed low speed, or a fixed full speed, or your own custom-designed speed "curve". Which way is yours configured?
 
Nov 17, 2020
18
0
20
1
My temps are completely fine. 40 and below at idle. its just the noise because its kinda spinning at a higher rpm. Asrock has a tool that runs a fan test to see what the minimum fan speed can be without affecting the cpu temps too much. I think I set it too 42 and below spins at 1375 because thats the 10% percent mark of what my motherboard THINKS the max rpm is. 50% fan speed at 60c which is 1880 rpm. Then it goes up to a slightly higher ratio from there. I once got the cpu cooler to be at 600rpm, can't remember what I did.
 

ASK THE COMMUNITY

TRENDING THREADS