Hello, I need a new battery backup for me new rig. I get a few brownouts and want the protection. the power supply to me pc is 650w do I need a backup with the same wattage or what is the right amount? I read that the backup doesn't need to be the same wattage is this true? any advice would be great thanks.
The "650W" is output power. To find out the input power, you need to know the efficiency and multiply the wattage. For example, a 500W power supply with a 90% efficency rating would require 556W input power. Also, this is the power used at full load; if your system only uses 300W of the 650W available, you will be using only about 350W input power (assuming 90% efficency). Also, too much backup wattage is not a concern...a 1000W unit would not cause you any problems even with a 200W power supply.