I found a funny workaround to this while experimenting. My Asus Z270E Gaming NIC shuts down my TP LInk TL-SG2210P switch as well as a Cisco SG208P if connected to one of the PoE Enabled ports on that one (but works fine on the non-PoE ports).

If I disable PoE on the SG2210P it still shuts the switch down when connected to the Asus board's NIC. I was wondering if I could fashin some sort of coupler that would make it work and then my eyes fell upon an item on my shelf that sort of couples two cables..I have this old TP Link PoE Injector just lying around.

Tried connecting it in series for a laugh to see what would happen.

It only bloomin works!

PC connected to "Ethernet In", Switch connected to "PoE Out" - yeah, backwards, and that works. The Injector isn't powered, no psu connected. Maybe there's a diode or something in there that filters it. That'll do for now.

I did at one time have the PC connnected to a Netgear GS108TP as well and that didn't shut the switch down but it overheated tremendously and at the time I had no idea why, and thought the switch just ran how. I'm guessing there was a short circuit the whole time and it was eating way more current than it should have.