How to control case fans based on CPU temps, not MB?

r33hab

Prominent
Jul 21, 2017
2
0
510
Hi,
I recently finished my build, which includes Gigabyte z170 HD3 and 4x 3pin fans. The MB has 1x4pin CPU fan; 2x4pin Sys_fan 1/2 and 1x3pin Sys_fan 3, so I use Y-splitters on headers 1 and 2.

In Bios I can set the fan curve (normal, silent, full speed, manual), but I think it's based on temps from sensors on the MB, not the CPU sensor, because in HWMonitor when stress-testing with Aida64 the 4 case fans' RPM remain the same as while idling.
So is there a way to make case fans (and their curve) follow CPU temps instead of MB? Right now there's no point in that curve, because MB temps barely change and fans don't speed up, only the CPU fan does.

I tried SpeedFan, but my fans don't show up there (or I can't find them) and the other option I'm considering is the fan headers on my Graphics (Strix 1080). That way I can at least control them based on GPU temps, but 1) I prefer CPU and 2) More visible cables...
Thanks!
 
Your Mobo manual (page 26) clearly states that the fan curves on BIOS are set according to system temperature. Those temps are measured on the Mobo, not on/inside the CPU. If that is not to your liking, you better get a Mobo that lives up to your requirements. It is however my experience that case fans ususally are handled by Mobo temps.

Nigel
 
Another option it to buy a fan controller and plug all your fans to it. The fan controller will come with a sensor you place under or near the CPU to read temps.

You then can place it in automatic mode or make manual fan curves with it to suit your needs.

I use this controller. It's pretty awesome.

https://www.newegg.com/Product/Product.aspx?Item=N82E16811992013&cm_re=fan_controller-_-11-992-013-_-Product

it's also worth mentioning the difference between 3 and 4 pin fan headers. They allow for that type of controlling.

However, you can handle that by using a fan controller instead of replacing the fans with proper pins.
 

r33hab

Prominent
Jul 21, 2017
2
0
510
First thank you for the answers!
Yes, based on what I've researched so far, I need to either find a MB that has the option to choose between CPU or system temps; or use a hub.
Apparently the GPU is not a good solution, because the case fans connected to it will behave like the GPU fans - meaning they won't spin at all until GPU reaches 60 C. It would have been nice to able to set a separate curve.
I'll look some more into it.