[SOLVED] Why won't fan speed change?

swanepoellukas5

Prominent
Jan 4, 2018
14
0
510
0
So awhile ago, I built my first gaming pc. I did extensive research on pretty much everything and as far as I know I didn't do anything wrong. BUT, the fans were uncontrollable. Literally. Assin, I couldn't controll the fan speed. I was fairly certain that it was a motherboard problem, because after testing the bios' "fantastic tuning", and than using 3rd party software like speedfan, neither solution changed the fan speed, and the pc is constantly running at ~30db. So I had the motherboard replaced and the retailer I bought it from said they sent it to back to ASRock and ASRock then replaced it. Problem still ain't solved. O, yeah, forgot to mention, the motherboard is a ASRock B250m-HDV. Literally the only reason I bought the this motherboard specificly, is because it has an extra 4pin motherboard header, sothat I can power and control 2 case fans. Ironic, right? Anyway, in the bios it says the fans are all running at their max. Any help? Please? Is it possible that the fans just run at max in bios, then revert to the fancurve when in windows, and the reason I get the permanent fan drone is because my fans are low qualtiy and the case is badly designed? I have 2 Corsair AF120 "quiet" editions(3pin casefan), a deepcool gammax 200T(cpu cooler, fan's 4pin), and a Corsair 88r mATX case
 

Nigel Spike

Reputable
Jan 9, 2016
560
1
5,365
157
Your motherboard has 4 pin fan connectors, while your fans only have 3 pin. The fourth pin is for PWM, so missing that you have to use DC mode. Page 62 in your motherboard manual describe where to find it, but is very vague on details. Go into UEFI and set it to DC , and try to set up a fan profile.
 

swanepoellukas5

Prominent
Jan 4, 2018
14
0
510
0
O crap! Sorry! I didn't see your reply earlier! I thought I turned the email notification on. O, and thanks, I'll give that a shot. I appreciate the reply, by the way
 

swanepoellukas5

Prominent
Jan 4, 2018
14
0
510
0
I checked the manuel and it's not exactly helpful. It's the Spanish section and I assume it's about what the 24 pin is for. LOL. I then looked for stuff on fans in English section and still found nothing on DC modes. O, and in the UEFI, I can only find options for monitoring the cpu or mobo temp, preset fan curves, or custom. BTW I use the fan curve options under the "HW monitor" catogory in advanced mode, and the tool is called FANTastic tuning. Is this the correct spot in the bios?
 

swanepoellukas5

Prominent
Jan 4, 2018
14
0
510
0
Thanks, but nope, sorry, only "modes" are preset fan curves(silent, standard, performance, fullspeed) and custom. And the only options for custom are to set 5 temperatures on a fan curve, and choosing to monitor the cpu or motherboard. Also, Nigel Spike, I found a .pdf file that contains the full motherboard manual, or so I assume, and there was infact information on p.62 about fans,but nothing about DC or PWM mode, just telling the user to choose a preset or custom fan curve. Sooo, yeah, I've given up hope at this point. If anyone has a breakthrough, I'm all ears. Just one more thing, what does the option to monitor the cpu/mobo temp actually mean? Does it literally monitor the actual mobo's temp or does the mobo have it's own censors, and the fans change speed based on the mobo's reading on the components, as opposed to the cpu's?
 

Karadjgne

Titan
Herald
There's several sensors on any mobo, the higher end, the strong possibility of more. You'll find sensors for VRM's, Northbridge, ram, chipset, Sata, pcie, zones etc all depending on exactly which board and which software is used to read it. Mostly it's internal bios code and not really read by software versions, but some like HWInfo or Hwmonitor will and you'll get tmpin1-tmpin10, none of which make any sense and can often be seriously wrong. On my mobo tmpin4 is read as 255°C and tmpin6 is -125°C both physically impossible.

But bios is always right. So changing between mobo/cpu will change what base sensor is used. There's probably an area sensor near the front intake (lower right) so you can set the intakes as case temp or cpu temp specific and fans will respond to that with that fan curve.

At this point I'd contact ASR support and ask them specifically if DC 3pin fans can be used, as in the headers will control either, or if they are pwm only and is that switchable
 

ASK THE COMMUNITY