Zotac loud idle - pwm converter?

degreal

What's an ITX?
Original poster
New User
Nov 27, 2019
1
0
I learned that Zotac 2070 Super mini has minimum RPM of 33% and has no way of lowering it. No need for such loud cooling while GPU temperature is practically ambient.

Solutions:
1) BIOS fan table modification - I guess nobody has managed to reverse engineer that.
2) MSI BIOS on Zotac - Nope.
3) Using Speedfan and case fan headers - OS dependant and messy setup.
4) Arduino based PWM converter - does this product exist?
Arduino is intercepting 25kHz PWM signal and converts it according to hardcoded table:
inputoutput
015
2015
4015
6040
8080
100100

Would this naive converter workor Zotac would detect it's being fooled?
 

eiselx86

Trash Compacter
Oct 23, 2017
46
22
It should be able to read the signal and output what frequency the card sings at. If you figure out at what range the fan operates within it should be quite easy to format a table to convert the signals in to a value (ex. 0-255, 0-1023 etc).

Don't know of any "ready to use" product that does exactly what you want. But the Arduino itself can be used to read the signals so you might not need any extra hardware. Easiest way would probably be to pull a pin high/low or analogRead to display a value between 0-1023. Depending on frequency range of PWM you might be able to get good results only using ADC.
To display frequency in hertz you use interupts and timers to sample/write the value. It uses different registrers to store, compare and capture the PWM frequency. Haven't done much in terms of PWM so I won't try to explain it further than that ? it involves more code and mo problems
 
Last edited:

Stevo_

Master of Cramming
Jul 2, 2015
449
304
There's multiple projects doing similar on the arduino forums(and sample code), there seems to be an issue from the Intel PWM spec that duty cycle below 20% is not supported and many fans cutoff around 30%. I think the answer was to lower the 12V fan power in conjunction with duty cycle to go lower.

https://forum.arduino.cc/