Hi, for some time, I designed my own hardware. It is a simple PWM Controller for PC fans. My PC motherboard has 4 pins PWM connectors, and I want to control the speed of fans, including a stop of them all. To build a semi-passive PC that is completely silent when I am watching TV. I found this idea on Tech Power Up site. So the idea is not mine, but the implementation and design of the solution are. I am in the middle of making this prototype work. I started with an order designed to be my PCB board, and I have all equipment to make this piece of analog hardware.
My first several tries of making PCB board failed so I found on the Internet Fabryka PCB web site of producer of PCB boards, with option to order professionally made PCB boards for prototyping. And I have it. And in near future I will bring my idea to live ;).
I designed my board to have 4-pin connector inputs from motherboard and 3 pin connector outputs for fans. In the middle are places for TIP NPN transistors and 10k Ohm resistors. And on the front panel will be 10k Ohm potentiometers for manual fan tuning. And that solution is for 5 fans regulation. I order also cover that fit exactly 5.25’’ place in my PC case to have this PWM controller.
There is one more thing. I find out that I can once put potentiometers to correct values and scale my hardware to completely stop my PC fans when the PC is in IDLE. In other words, they do not use CPUs or GPUs. And that is the unique value of my idea. It is not only PWM Controller. It is a Semi-Passive add-on for my Dream PC. Feel free to comment if you have questions and/or like this idea. Thanks!