Caveat: This answer focuses on the computer components, not other devices Which may even be powered by the UPS. I've witnessed occasional stories of non-sine wave power being incompatible with selected other gadgets. A UPS unit for your router and modem can also be good through a power outage since https://pantip59146.thezenweb.com/the-smart-trick-of-uninterruptible-power-supply-ups-that-no-one-is-discussing-71832676