Weird fan behaviour

Hardware Cooling
1

Hey,

 


so I've been undervolting my CPU on the weekend and it seems to be stable at 1V. But I encountered a problem with my main CPU fan in the process of undervolting. It randomly ramps up to 100% and stays at 100% for a random amount of time (sometimes for hours) and then suddenly ramps down again to around 700-800 rpm. I didn't change anything in the BIOS other than the CPU VCore. The temps are low and there is no reason at all for the fan to ramp up.






I tried loading the default profile for the BIOS, but it didn't help and now I'm kind of clueless. Did I somehow manage to corrupt my BIOS?


Intel i5-4670
Gigabyte Z87-D3HP
G.Skill Ares 8GB DDR3-1866
Gigabyte GeForce GTX 770 WindForce 3X OC
Cooler Master G600 600W


Already searched on google quite a bit, but couldn't find anything.

 

Some BIOS settings:

y1BCXEH.png960x720 1.29 MB

AMvIJy1.png960x720 1.18 MB

 


Regards,
Pp

2

Have you looked at the task manager when it does this to see if there is some process using the CPU?

3

The CPU isn't being used at all. And even if, my cooler is totally overkill. When it is not spinning at 100% and I put some load on my CPU it spins up to 1000 rpm MAX (100% is around 1800-1900 rpm).

4

Ok, I've tried updating the BIOS. The BIOS looks a lot better now, but it didn't fix the problem. But what seems to have fixed the problem is simply switching the OPT_CPU fan with the main CPU fan. No Idea what's that all about, but if it keeps working I'm happy.