Accurate PSU Watt Usage. Kill-A-Watt or something better?

[TheSlySyl]

I want to get an accurate rating of how much total wattage my PSU is using. I'm expecting to buy some sort of external monitoring hardware to do this, as I don't know of any software way to monitor my full wattage including all my hard drives and peripherals.

Is a simple Kill-A-Watt good enough if I put it between the wall and the PSU? Or is there a better way?

 

[mnewxcv]

Kill a watt works fine. Or a ups with a digital display.