Do I need a UPS or surge protector?

[Ganso]

I don't care about unexpected shutdowns and losing unsaved data but I don't want my system to take any damage from unexpected events. My PSU is a Seasonic M12II 620W. In the meantime is it a poor idea to plug directly into the wall?

 

[WyomingKnott]

Depends on the weather where you live. If you ever have lightning (this is irony; everyone has lightning) then surge suppression on power and on network connections is a good idea.

I once had a nearby lightning strike fry every Ethernet connection that had a cable attached. Only those ports; I was left with a hub with three dead ports and the three that were unoccupied working fine. Also blew out the HDMI ports on my TVs. I use surge arrestors on Ethernet ports now.

 

[westom]

I once had a nearby lightning strike fry every Ethernet connection that had a cable attached. ... I use surge arrestors on Ethernet ports now.

Says nothing about protection from destructive transients. That example only says a homeowner all but invited lightning to hunt for earth destrutively inside the building. Damage because a proven and less expensive solution was not installed.

If located adjacent to an appliance, that protector must somehow block or absorb a surge. How does a 2 centimeter part inside the protector stop what three miles of sky could not? It doesn't. How does a protector, rated at hundreds of joules, absorb a destructive surge that may be hundreds of thousands of joules? Will that undersized protector avert damage from future surges? Read manufacturer specification numbers. Of course not.

Facilities that cannot have damage routinely connect directly to AC electric wiring. And use a completely different and proven solution. Unfortunately, that different device is also called a surge protector. Properly installing it means destructive currents need not enter a bulding. Critical is a low impedance (ie 'less than 10 foot') connection from protector to single point earth ground. Only 'whole house' protection means protection from all types of surges - including one type that is typically destructive to Ethernet ports.