I'm not really sure on what to say in the way of a UPS. I have two systems, one with a 500W PSU and one with a 750W PSU. I want a UPS for the both of them. Thing is, when searching for one, it shows "360Watt" or "300Watt". What do I need to look for to support both of my systems? I want one due to the fact that the power in out house is very unstable and don't really want them directly consuming the power from the wall. I've tried a surge protector, seems like it wasn't enough. Can someone help? I'm in the UK