On Monday, December 14, 2020 at 6:53:21 PM UTC-8, danny burstein wrote:

Ahhh... another of my Mac Mini's says it's an a-1283.

I didn't realize until today they were different models.

I've certainly used them with the tops off, but can't exacly
swear that it was the a-1283.

OK. With the tab at the bottom of the well shorted to the perimeter
shield it still won't boot. Resetting the NVRAM doesn't help. I'll try
re-seating the CPU. At present I have no further ideas.

Thanks, ... P.