SOLVED Noctua fans don't reach top rpm

[mrd]

Just finished a new build (see sig) and after reading the posts on fan control I started doing my burn-in tests. The excellent posts on fan thresholds worked like a charm, preventing any stalling. The raw commands used to set fan profiles/per-zone duty cycles also seem to work.

The issues is, that my 2 Noctua NF-A14 iPPC 3000PWM fans won't get above 1500/1600 RPM, even after setting the fan profile to full and running prime95.

Noctua fans are connected to the FAN4/FANA headers on the mobo. I plan to buy another 3x120mm noctua fans to replace the case fans of which only 2 are connected right now (they're 3-pin fans).

I'm using a linux livecd's for testing, together with ipmitool. The rpm's are confirmed by the ipmi sensor readings in the web interface.

Show : Idle Sensor Reading

Code:

# Sensor reading with fan profile set to standard
root@ubuntu:~# ipmitool sensor list
CPU Temp  | 24.000  | degrees C  | ok  | 0.000  | 0.000  | 0.000  | 95.000  | 100.000  | 100.000   
PCH Temp  | 31.000  | degrees C  | ok  | -11.000  | -8.000  | -5.000  | 90.000  | 95.000  | 100.000   
System Temp  | 26.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 80.000  | 85.000  | 90.000   
Peripheral Temp  | 36.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 80.000  | 85.000  | 90.000   
VcpuVRM Temp  | 32.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 95.000  | 100.000  | 105.000   
FAN1  | 1000.000  | RPM  | ok  | 300.000  | 500.000  | 700.000  | 25300.000 | 25400.000 | 25500.000
FAN2  | 1300.000  | RPM  | nc  | 500.000  | 600.000  | 700.000  | 1300.000  | 1400.000  | 1500.000  
FAN3  | 1300.000  | RPM  | nc  | 500.000  | 600.000  | 700.000  | 1300.000  | 1400.000  | 1500.000  
FAN4  | 400.000  | RPM  | ok  | 100.000  | 200.000  | 300.000  | 3000.000  | 3100.000  | 3200.000  
FANA  | 400.000  | RPM  | ok  | 100.000  | 200.000  | 300.000  | 3000.000  | 3100.000  | 3200.000  

Set fan mode to full and check again.

Show : Fan mode full

Code:

root@ubuntu:~# ipmitool raw 0x30 0x45 0x01 0x01
root@ubuntu:~# ipmitool sensor list
CPU Temp  | 24.000  | degrees C  | ok  | 0.000  | 0.000  | 0.000  | 95.000  | 100.000  | 100.000   
PCH Temp  | 31.000  | degrees C  | ok  | -11.000  | -8.000  | -5.000  | 90.000  | 95.000  | 100.000   
System Temp  | 26.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 80.000  | 85.000  | 90.000   
Peripheral Temp  | 36.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 80.000  | 85.000  | 90.000   
VcpuVRM Temp  | 32.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 95.000  | 100.000  | 105.000   
FAN1  | 2000.000  | RPM  | ok  | 300.000  | 500.000  | 700.000  | 25300.000 | 25400.000 | 25500.000
FAN2  | 1200.000  | RPM  | ok  | 500.000  | 600.000  | 700.000  | 1300.000  | 1400.000  | 1500.000  
FAN3  | 1300.000  | RPM  | nc  | 500.000  | 600.000  | 700.000  | 1300.000  | 1400.000  | 1500.000  
FAN4  | 1600.000  | RPM  | ok  | 100.000  | 200.000  | 300.000  | 3000.000  | 3100.000  | 3200.000  
FANA  | 1600.000  | RPM  | ok  | 100.000  | 200.000  | 300.000  | 3000.000  | 3100.000  | 3200.000

Start prime in another window, wait for temps to rise and check again.

Show : Load Sensor Reading

Code:

root@ubuntu:~# ipmitool sensor list
CPU Temp  | 77.000  | degrees C  | ok  | 0.000  | 0.000  | 0.000  | 95.000  | 100.000  | 100.000   
PCH Temp  | 36.000  | degrees C  | ok  | -11.000  | -8.000  | -5.000  | 90.000  | 95.000  | 100.000   
System Temp  | 33.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 80.000  | 85.000  | 90.000   
Peripheral Temp  | 37.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 80.000  | 85.000  | 90.000   
VcpuVRM Temp  | 62.000  | degrees C  | ok  | -9.000  | -7.000  | -5.000  | 95.000  | 100.000  | 105.000   
FAN1  | 2300.000  | RPM  | ok  | 300.000  | 500.000  | 700.000  | 25300.000 | 25400.000 | 25500.000
FAN2  | 1200.000  | RPM  | ok  | 500.000  | 600.000  | 700.000  | 1300.000  | 1400.000  | 1500.000  
FAN3  | 1300.000  | RPM  | nc  | 500.000  | 600.000  | 700.000  | 1300.000  | 1400.000  | 1500.000  
FAN4  | 1600.000  | RPM  | ok  | 100.000  | 200.000  | 300.000  | 3000.000  | 3100.000  | 3200.000  
FANA  | 1600.000  | RPM  | ok  | 100.000  | 200.000  | 300.000  | 3000.000  | 3100.000  | 3200.000

Am I doing something wrong, or are both fans damaged? Another theory I have is that the _reported_ speed is halved, thus explaining both my low rpm at idle and load (wishful thinking).

 

[Stux]

Or are your fans actually a different model?

Is the fan hub sticker correct?

Other Noctua 140mm fans rotate at 1200rpm, so 1500rpm is certainly the right range for a different model.

Did you check out my hybrid fan control script?

 

[mrd]

Or are your fans actually a different model?

Aaaaand we have a winner. Ofc this was a PEBKAC. These are 24V fans, while the mb header is 12V. A pity though... I'll have to ship these back to amazon, with freight costs exceeding 50% what I paid for 'em.

Did you check out my hybrid fan control script?

Only in passing. I'm due for a 2h commute soon and I'll take a more indepth look. Might even make a python rewrite :).
Thanks a lot!