- Buying a new UPS for your PSU and keeping the monitor plugged into existing inverter is the sensible way.
- If you want to buy a new higher capacity inverter then make sure you account for any new devices you’d be adding to your inverter backup in near future.
I use some pretty old 3KVA Luminous inverter. Most of the times it switches pretty fast on inverter mode to not affect the PC. But the UPS mode works flawlessly.