Pulsing fans on GIGABYTE board

[mattiaunola]

Hello,


I am getting weird fan behavior with the GIGABYTE MZ72-HB2 board. Fans are cyclically ramped up/down every ~10 seconds. This is odd since the min. fan speeds I see in BMC are all above the minimum and minimum critical fan speeds defined out-of-the-box in the CPU and SYS fan profiles.


My setup is:


GIGABYTE MZ72-HB2
2 x EPYC 7542
2 x Noctua NH-U9 TR4-SP3 coolers


CPU fans are connected to the boards CPU_FAN connectors.
Boards SYS_FAN connected to a chassis fan hub.


I tried lowering the min. limits of the fan profiles. It did not help.
I tried disconnecting chassis fans so that only CPU fans are active. CPU fans still cycle up/down.

BIOS and BMC SW versions are quite recent.

Has anyone else had this problem and if so, how was it solved?

 

[osmarks]

I have a similar issue with an MS03-CE0. Increasing the minimum fan speed seems to make it do this a lot less. I'm not sure why. Overly aggressive thermal protection?

 

[osmarks]

I figured it out, I think. On the "edit fan profile" screen:



the "policy" dropdown lets you select a second configuration to be applied in some conditions. It seems like it was switching to that second configuration for unclear reasons, because when I set it to match policy 0, the spinups stopped.

Edit: They didn't stop entirely, so I suppose it's not entirely that? Very strange.

 

[RolloZ170]

2 x Noctua NH-U9 TR4-SP3 coolers

Has anyone else had this problem and if so, how was it solved?

use other FANs with more min. RPM
or change min.lower thresholds.
the ramp up to max. is BMC panik, thinking FAN is blocked by an small animal...

 

[osmarks]

I get fan spinups intermittently. If there's a minimum RPM, why would it complain seemingly randomly? Also, ipmitool lists 150 and 300 RPM as minimum thresholds for something or other, and the fans are apparently above that.

 

[RolloZ170]

I get fan spinups intermittently. If there's a minimum RPM, why would it complain seemingly randomly?

i did not replied to your msg.

 

[RolloZ170]

the "policy" dropdown lets you select a second configuration to be applied in some conditions.

new policy adds one. you can select policy 1 then and control a single FAN with other sensor source.
this is because you can only run ONE FAN profile at a time.

 

[RolloZ170]

make sure you control all connected FANs,
all with one policy or use multiple policies.