I am a happy owner of a TSW200 switch in a low-traffic and low-power network. It is fast, requires no configuration, powers several devices in the network, doesn’t break others, consumes little, and stays cool.
That switch has recently refused to accept a computer into the network with an Azuz Prime Z270-K motherboard and an onboard Intel I219-V Gigabit LAN. When the Ethernet cable is connected, the switch stops all traffic. All its LEDs go dark. Then, they start blinking in unison with consistent pauses between blinks. Of course, I tried powering the switch off. I also tried changing the patch cord. The motherboard can be connected directly to the router but not to the switch. I mitigated the problem by introducing a spare router in access point mode as a non-PoE switch between the computer and the TSW200.
I also had other issues with this motherboard, so I am suspicious. I am considering buying a PCIe Ethernet card to avoid using the onboard port. Could there be any recommendations for compatibility requirements that I should look for when shopping for a networking card or a replacement motherboard? Or should any new card of appropriate quality work? Then, testing seems the only option.
While the wiki pages have some information on the compatibility of PoE devices, it does not seem to address the described situation.