Technology Explained

How Much Energy Does Your PC Use? (And 8 Ways to Cut It Down)

Georgina Torbet Updated 18-12-2019

As people become more aware of the impact of their actions on the environment, one issue to consider is how much electricity is being used by your computer. And as you have to pay for electricity use, you might be concerned about how much your PC use is costing you as well.


But how much power does a PC really use? And how can you cut this power use down?

How Much Power Does a PC Use?


The power usage of a PC depends both upon its hardware and on how often it is used. A PC that is always on and is constantly mining for cryptocurrency, for example, will use far more power than a PC which is turned on once a day and used for a few hours for checking email or browsing the internet. And leaving a computer on overnight will use energy just as much as using it during the day.

A study by the Energy Saving Trust found that computers and their peripherals accounted for around 8 percent of all home electricity usage in the UK, with a further 25 percent being used by other consumer electronics. That works out to an annual cost of around £35 per person spent on electricity for a PC, which is equivalent to nearly $50 per year in US dollars.

The report also shows that a PC uses much more energy than a laptop—almost six times as much—because laptops are optimized for battery life in a way PCs are not.


One common use for PCs is gaming, and the energy consumption of a gaming PC is different from that of other PCs because of the more advanced hardware. A 2019 report by the Berkeley Lab looked at 26 different systems running 37 games, to see how much power different platforms used.

They found that there was a large range of power usage between gaming systems, with them using anywhere between 5 kilowatt-hours per year all the way up to 1200 kilowatt-hours per year. In general, PCs drew more power than consoles like Xbox One or PS4.

But the biggest factor in the amount of energy used was not the format of the gaming system, but rather its GPU. More powerful GPUs use considerably more electricity.

What Are the Different PC Power Modes?

Manage Windows 10 power options to determine power consumption


PCs do come with functions to help reduce power consumption. You may not want to turn your PC off when you’re done with it, for example because you don’t want to wait for it to boot next time you need it. In this case, you can use the Sleep or Hibernate functions.

Sleep mode, also known as suspend, puts the computer in a low-power use state. The computer will use the RAM to save your current open documents and application data, so you won’t lose anything when you enter sleep mode. The computer can also wake up again quickly. But power will be cut to components not being used like the display, storage, and peripherals.

Hibernate mode is a little different, as it cuts power to the RAM as well as the other components. Instead of the data about current states being saved on the RAM, it’s saved to the storage instead. That means that the computer is using essentially no power, as if it were turned off. But it will still remember what you were last doing when you turn it on again.

Sleep mode is useful when you are taking a short break from using your computer. Hibernate is better if you plan to leave your computer overnight. Windows 10 doesn’t show an option to hibernate by default, but you can add hibernate to the start menu How to Add Hibernate to the Windows 10 Start Menu By default, the Windows Hibernate option isn't readily available in the Start Menu. Here's how to add it for quick access. Read More yourself.


Which PC Parts Use the Most Power?

Some PC parts use more power than others

The exact amount of power used by a computer varies depending on what parts are inside. Some machines, like high-end gaming desktops with multiple graphics cards (GPUs), will use much more power than a low-wattage machine with fewer components.

However, it’s not the case that newer, better hardware necessarily uses more power than older, less good hardware. In fact, one big issue for hardware manufacturers is power efficiency. Manufacturers work to make their components more efficient. So if you have an older processor, for example, it may actually use more power than a newer processor would.

In general, it is the processor and graphics card(s) which use the most power. The motherboard and power supply do draw power, but they pass on this power to other components so you needn’t concern yourself with their power consumption.


Other components like RAM, hard disk drives, solid state drives, fans, case lighting, and optical drives also use some power, but not a large amount. The power use of peripherals like keyboards and mice is generally below 0.5W so it’s not worth worrying about.

As a rough guide, here are approximate ranges of how much power is used by each component:

  • CPU: 55 to 150W
  • GPU: 25 to 350W
  • Optical Drive: 15 to 27W
  • HDD: 0.7 to 9W
  • RAM: 2 to 5.5W
  • Case fans: 0.6 to 6W
  • SSD: 0.6 to 3W
  • Other hardware components: N/A

And here’s the power draw of the components which pass power on to other parts:

  • Power Supply (PSU): 130 to 600+W
  • Motherboard: 25 to 100W

For reference, an oven uses around 1000W, a vacuum cleaner uses between 500 and 1200W, and a games console uses between 45 and 90W, according to the Centre for Sustainable Energy.

How Can You Reduce the Power Used by Your PC?

If you’re concerned about power usage, there are several things you can do to lessen the amount of power your computer uses.

Choose Power-Efficient Hardware


  1. Upgrade older mechanical hard drives to solid state drives. They are both faster and more efficient with power consumption.
  2. Unless you’re doing something that requires the extra power like gaming or video editing, stick with onboard graphics adapters. If you have to install a video card, get something with less power. Remember, the more cooling a component requires, the more electricity it’s going to need.
  3. Replace your hardware, period. If you have the opportunity, upgrade to newer components to boost performance and efficiency.
  4. If you don’t need a powerful computer, try swapping to a low-wattage version Build Your Own Low-Wattage PC with Three Simple Design Rules After a few failures and experiments building my own fanless, highly efficient computer, I can share three low-wattage builds designs that dispense with most moving parts and minimize the number of fans used. Read More . Look at a small HTPC or media device, or even an HDMI stick PC.

Change the Way You Use Your PC


  1. Turn off your computer when you’re not using it (such as in the evening or on the weekends). If you’d rather have it boot faster 6 Ways to Fix Slow Boot Times in Windows 10 If your Windows 10 boot time is slow, you aren't alone. We've compiled the most common solutions to help you fix slow startup on Windows 10. Read More , you can use Sleep or Hibernate instead of shutting it down completely.
  2. Either turn your monitor off completely when you’re not using it, or have it enter a suspend mode. While in suspend, the screen will be completely black, but as soon as you move your mouse or press a button on the keyboard it will spring back to life. Screensavers do not save power, so there’s no point in using them unless you like the look.
  3. If you have an older machine, in the BIOS check the “ACPI Suspend Type” option and make sure it’s set to S3 as opposed to S1 or S2. This will prevent the computer from powering the CPU, RAM, and several other components when it’s in sleep mode.
  4. In Windows 10, under System > Power & sleep How to Use Your Windows 10 Power Button You can shut down Windows using the physical button on your computer or the commands on the Start Menu. We explain what these options do and how to tweak them. Read More , you can change several power saving settings including how and when your computer sleeps. This will allow you to automate the low power modes.

Reduce Your PC’s Power Usage

With these tips, you can reduce the power used by your PC. That’s good for the environment and for your wallet.

To learn more about this topic and how much power is used by different components, see our guide to how much power your PC needs How Much Power Does Your PC Need? Computers need power. They turn it into heat, noise, and light -- like magic. But how much power does your PC need, exactly? Let's find out where all that power goes... Read More .

Related topics: Computer Maintenance, Computer Parts, Energy Conservation, Green Technology, Save Money.

Affiliate Disclosure: By buying the products we recommend, you help keep the site alive. Read more.

Whatsapp Pinterest

Leave a Reply

Your email address will not be published. Required fields are marked *

  1. dragonmouth
    December 18, 2019 at 5:45 pm

    "A study by the Energy Saving Trust...."
    Using statistics, one can justify any position.

    "Replace your hardware, period."
    If I have to spend $400-$500 for an inexpensive computer to save $100 of electricity, the math just doesn't work out.

    Unfortunately, any electricity saving efforts are overwhelmed by the global population increase and concomitant need for more energy. The rate of increase of the population far outstrips the rate of increase of electrical capacity.

  2. kevin go
    April 4, 2017 at 9:23 pm

    So his mathematics are flawed, but is implied is correct.

    If you are at a pc with a printer for usage, say,
    6 am to 6 pm, during that time you will have 1 hour break, a mid day meal for example.
    So if you turn the system OFF for that break and after your shift, that's 13 hours with no power usage, that has got to save money, multiply that by the amount of systems used by a firm.
    In a year you will have saved enough money to run the same systems for another year, with the money you saved this year.

  3. lordmogul
    June 15, 2016 at 3:47 pm

    Well there is one miscalculation: The listed power consumptions are the rated "maximum" draw. Or to be more precise the TDP.

    Most modern GPUs and CPUs power down in idle to less then 15W
    On average a "normal" desktop system will draw less than 100W when left alone running.

  4. Roger Williams
    June 15, 2016 at 11:18 am

    No mention of smart power bars. When I turn off my computer the peripherals all shut down, including my wireless phone base. The power hog is the cable PVR that is on 24/7 because it takes so long to boot.

  5. epiquestions
    June 15, 2016 at 6:01 am

    how does a motherboard consume more power than a processor? lol.

    • Gary
      January 12, 2017 at 5:44 am

      Not necessarily consume. You're forgetting that the motherboard transfers power from the PSU to the CPU. Most GPUs, CPUs, fans, etc, are dependent on your mobo for power. Some GPUs have there own independent power connector though but they still draw power from the PCie slots

  6. Anonymous
    June 15, 2016 at 4:33 am

    I have written it before & will write it again: in its drive to be in readers' face more frequently MUO has been on a recruitment drive of late. The result: more non-value adding articles & articles like the one above, which shows the author's lack of understanding.
    It seems editor Tina Sieber is refusing to accept the reality. Maybe something needs to break before she and/or MUO will react constructively.

  7. Davey
    June 15, 2016 at 2:45 am

    The author seems not to understand the subject very well. A PSU rated at 450W doesn't consume 450W--it can merely supply that amount of power to the other devices in the PC. A unit with a 450W PSU might need to supply (not consume) only 350W when working on a processor-intensive task--the PSUs are usually sized to exceed the maximum anticipated load. The PSU would perhaps consume 35W (it's not 100% efficient, so some power is lost in heating the PSU). At idle, this PC would consume even less power, maybe 150W (including the PSU)? Leaving it on overnight, it would be running at idle most of the time. Various sleep/suspend modes shut down more of the PC, so if that has been enabled in the power configuration section, even less power would be required.

  8. Anonymous
    June 14, 2016 at 11:15 pm

    Increase in energy demand and consumption is the price for technological progress. New energy users are coming online faster than the old users can make their use more efficient. There are basically two ways to solve the problem. Either drastically reduce the number of users or drastically increase the supply of energy. The former can be achieved through a global war which even the environmentalists will not appreciate. The latter is not going to happen because of the environmentalists' dogged insistence on "saving energy" and their obstinate opposition to new power plants.

    "By reducing how much power your computer consumes, you could save anywhere from $20 to $200 dollars a year."
    If it is going to cost me $300-$400/yr to save $20-$200/yr, I'll pass, thank you. I'll just keep using my old, inefficient PC until it falls apart.

  9. Anonymous
    June 14, 2016 at 11:08 pm

    My PC is set to go to sleep after 20 minutes of inactivity.
    Of course, I turn it off at night when I go to bed.

  10. xD
    June 14, 2016 at 10:13 pm

    So the PSU uses from 130W to over 600W? You should be ashamed and not post articles you have no idea about.

    PSU consumes very little, most significant is actually loss due to efficiency which is being improved radically lately. Older PSUs, heavily used PSUs and cheap PSUs have lower efficiency in this case.

    For an example, my computer idles between 50..60W (16GB DDR3, i5-4670k, SSD + 2xHDD, GTX 960, 5 case fans). This doesn't incldude my monitors, peripherals and other related devices.

    • Anonymous
      June 14, 2016 at 11:18 pm

      "So the PSU uses from 130W to over 600W? You should be ashamed and not post articles you have no idea about. "
      Why be correct when you can sound good? If the authors gave us the correct numbers, then there would be no need for "the sky is falling, the sky is falling" article.

  11. Andrew
    June 14, 2016 at 9:01 pm

    I like my desktop to be on and accessible where ever I am, so to save power instead of keeping it on I put it to sleep and use WWLAN to turn it on when I need it.

  12. Anonymous
    June 14, 2016 at 7:58 pm

    Increased power demand and usage is the price of progress. When new users of power are coming online faster than the old users can make their use more efficient. there is no way there could be a reduction in power usage.

    "you could save anywhere from $20 to $200 dollars a year. "
    If it costs me $300-$400/yr to save $20-$200 then it isn't worth it. I'll be losing more money trying to save money then if I kept my "inefficient" PC.

    Let's be realistic. There are two ways to resolve the problem of increasing power consumption. Either drastically reduce the number of users or drastically increase the amount of power generated. With the environmentalists fixated on usage reduction by means of efficiency, there ain't no way on God's green earth that generation will be increased. As it is, each new generating facility has to be for tooth and nail.

  13. Anonymous
    June 14, 2016 at 7:20 pm

    Interesting to note....the story states an average of 80-250W of consumption. But then uses a picture of an iMac which only uses 63W. If you opt for a laptop, significantly less. I guess the averages are for Windoze desktops.