You would have to buy hardware specific for that purpose. These days you can get them at many hardware stores, people use them to see how much power major appliances are using.
You can see pictures of one in some of the Tom's articles, when they measure total power usage. They plug into the wall, and the PC plugs into them.
there are devices like this one power plug meter with which you can monitor your constant/average consumption in watts and cumulative KWH of your pc tower
You would have to buy hardware specific for that purpose. These days you can get them at many hardware stores, people use them to see how much power major appliances are using.
You can see pictures of one in some of the Tom's articles, when they measure total power usage. They plug into the wall, and the PC plugs into them.