The USB port on your computer can be quite a center of activity. Between reading USB drives, charging external devices (like MP3 players) and serving as connection centers for wireless adapters, these drives certainly do a lot. To perform at a level which will keep pace with your tech needs, your USB drives require a lot of dedicated power. If you are interested in monitoring the power absorbed by your favorite USB-based devices, you can do so using pre-installed Windows utilities.
Go to your computer's Control Panel and then click on "System." A new window will pop up. Click on the "Hardware" tab and then select "Device Manager."
Click "USB" to display your USB ports and currently installed USB peripherals. Right-click on the "USB Root Hub" icon for the port you want to see the power information for.
Select "Properties" from the sub-menu. A new window will appear. Click on the "Power" tab to see all power flowing to the USB port, as well as information about dedicated power sources, and max power output.