I have tried it about a year ago on a PC motherboard and it worked...
Okay, so if it worked then, let's assume it still works. Did you double check the connection to the mac Mini switch to make sure you know which side is the "return" (i.e. which side is always at the zero volt level)? This must only be checked with the mac Mini off and unplugged and you are looking to find zero resistance between it and, for instance, the zero volt line of your SATA drive (or zero volt line of a USB connection). I would say the "black" connection, but of course all wires in the Mac Mini are black.
Also, what are you using to provide your 5V standby voltage from the Mac Mini?
I have checked and found the return on the mini, and I'm using the purple line from my pico psu as 5V stand by.
I just got another cube switch, and followed the instructions on the original post and it works perfectly!! Thank you so much for the amazing write up and help minihack!
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