There isnít an easy way to identify your Power Supply Unit (PSU) via software. But this is a simple enough task if you know what you are looking for. Open your computer case and look for the wattage from a manufacturer's label on the side of the power brick (PSU). Note - The PSU is the square block where the plug and power cable attach into.
DO NOT TOUCH THE PSU! It may contain residual charge and electrocute you even when everything is turned off.
For notebook power supplies, they are written at the back of the power brick. If you canít find it anywhere look for the Output Voltage (V). This figure is normally 19V for all notebooks. Also, somewhere near the Voltage figure you will find the output Amperage (A).
Multiply the Voltage figure by the Amperage figure and this will give you the PSU's power in Watts.
Below we have included an image that displays an example label on a laptop/ notebook.
Click on the image below to zoom in.
In the case displayed in this image we have 19V x 9.5A = 180.5 W