when you buy a psu, do you look at efficiency??
what is efficiency has to do with psus??
The higher the efficiency, the less electricity is wasted as heat, the lower the actual electricity drawn from the A/C outlet will be.
Example: All the component in a PC will draw a total of 300w at full load.
PSU #1: 70% Efficiency - Actual power draw from A/C outlet = 300w/70% = 428.5w = 128.5w wasted as heat.
PSU #2: 85% Efficiency - Actual power draw from A/C outlet = 300w/85% = 352.9w = 52.9w wasted as heat. slightly lower electricity bill too.