And then there's shit like this: https://www.amazon.co.uk/Standard-Computer-Quieter2-Quieter2Q-Quieter2D-Black/dp/B099RXXDYT

if you want to use it on the third part mini pc,confirm that the output voltage of your mini pc needs 12V. If the output voltage is lower or higher than 12V and the output current exceed 2A, it will burn your mini pc or cpu.