How to check a PC's power consumption
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Computers today come in many shapes and sizes. Consequently, the power they use (measured in watts) differs based on their components, model, and form factor. The following sections provide a few methods for users to determine how much power their desktop or laptop computer regularly uses.
To proceed, select a method from the list below or read through them all to see which best suits your needs.
Using a hardware monitor utility
This method for checking power consumption involves downloading and installing a free tool that shows you the real-time power draw of each component in your computer.
- Open your preferred Internet browser and navigate to the Open Hardware Monitor download page.
- Click the Download Now button.
- Click the downloaded file and follow the installation instructions.
- After installing and launching Open Hardware Monitor, you can expand each component's section to see how many watts it is currently using.
Using an online tool
There is a handy online tool offered by OuterVision that approximates your system's total power draw, provided you know the make and model of its internal components.
- Open your preferred Internet browser and navigate to the OuterVision Power Supply Calculator.
- Scroll down a bit and click the Basic tab (A).
- Fill out each of the component fields (B).
- Click the Calculate button (C).
- In the Results section, Load Wattage displays the estimated power consumption of your computer.
Using a wattmeter
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While a wattmeter does have an associated upfront cost, once purchased, it's a simple and accurate way to see your system's total power draw.
After buying a wattmeter (we suggest Amazon, Newegg, or your local computer store), plug it into the wall, and then plug your desktop or laptop power cord into it. The built-in screen displays how much power your computer uses in real-time.
You can use a wattmeter with other household electronic devices, such as a coffee maker or television.