How to Measure PC Power Consumption

How much power does my PC consume every month? How to measure PC power consumption? If you are wondering this, you are in the right place.

In this post, we are going to help you to calculate and measure the consumption of your PC through various methods that are quite simple to follow. Let’s go there!

Why would I want to know how much my PC Consumes?

We live in a context of unprecedented rise in electricity prices, which leads us to want to know what the devices we use daily cost us.

One of the device that consume the most will always be desktop computers, since they do not need a battery, they are designed to give the best possible performance by consuming electricity.

See Also: How much does a Gaming PC cost

So, in addition to teaching you how much your PC consumes, we are also going to review how to calculate PC consumption and what affect your home’s electricity bill each month will have, and how to reduce the monthly cost of using your computer.

Another very important reason to know the consumption of your PC is to find power supply compatibility. For example, a 1000W power supply may be overkill on most computers.

METHODS: How to Measure PC Power Consumption

There are several ways to know the consumption in watts (W) of your PC, and the ones that we are going to see either in measuring (knowing the consumption from exact data, measured directly to our PC, or in calculating (making an estimate based on consumption of the parts that our computer has). Both methods are potentially interesting, but we will see that they have big differences.

1. Direct Measurement with a Consumption Meter

The most precise and clear way to measure the consumption of a computer is with a consumption meter by plugging the power supply directly into one of these meters.

They will give us the value in W of current consumption in a precise, reliable and instantaneous way.

The downside of this method is, you would need to buy a domestic electricity consumption meter. The good thing is that there are many meters with good quality and prices.

In addition, there are meters that are smart, and allow consumption to be recorded over time to calculate energy expenditure through a mobile app.

For Example, if you have a UPS (uninterruptible power supply), you will surely be able to monitor consumption directly by using its official app

There are also power supplies with monitoring software, which will tell you the consumption in detail, but it is very rare.

Keep in mind that the consumption that we will see does not correspond only to the consumption of the PC parts (CPU, GPU, etc). Within the power supply, there are significant energy losses that lead to an increase in consumption.

See Also: How much Power does a Gaming PC Consume

If you want to know the consumption of the parts of PC without taking into account the contribution of the source, follow the other methods or subtract a percentage from this measurement.

2. Measurement on Laptops

If you want to know how much your laptop consumes, you can use this method to see the energy needed while charging and using the computer. However, this is typically limited by your laptop’s own power supply, so check its power.

3. Use an online Calculator

The third method we recommend is to use a consumption calculator to make an estimate based on the parts of the PC.

The problem with these types of calculators is that they indicate consumption under load, when we are playing something or doing some type of rendering.

This is a problem and if we want to estimate the impact on the electricity bill, It will be little difficult to check it. We tend to use computers in an idle state for more time than playing games or doing some kind of heavy loads.

What you can do is take this value to calculate the time you use your PC playing or in demanding tasks, and to estimate the consumption at rest.

4. Measurement via Software

Is it possible to check how much my PC consumes through software? Yes, it is possible, but only partially.  Almost all computers allow you to check the consumption of the processor and the graphics card through sensor measurement programs.

5. Add the Manufacturer’s Data

Another option we have to estimate consumption is to look for the information provided by the manufacturers of our graphics card and our processor, add them up and apply a reasonable margin of 50W, 100W or 150W, for example.

See Also: How to Choose Power Supply for Gaming PC

Specifically, we can check the TDP or TGP on the Intel, AMD or NVIDIA website depending on what components we have.

How to Calculate the Cost of PC Power Consumption

Once you have calculated the consumption of your PC under load or at rest, we can now estimate the monthly cost of using PC on our electricity bill.

The problem with these types of estimates is that they can give something too high and scare us, if we are not rigorous with the measurements we use.

The biggest problem is in the calculation of consumption is that there are always the correct figures. Anyhow, there are three ways to do this:

• We can use an intelligent consumption meter to know the total energy that our computer requires in a specific period. The idea here would be to have the PC connected to the meter for at least a week and extrapolate the value to a month, or directly leave it for a month making the measurements. The point is that the meter will add up the consumption progressively, so we will no longer have to estimate anything. In our article on consumption meters, everyone is capable of measuring energy consumption, not just the smart ones.
• If we have been able to measure the consumption of the PC with and without load, we can estimate the hours of daily use, using this real data.
• On the other hand, if we have not been able to make any precise measurements and we have to rely on calculations and estimates, we must be very careful not to go too far and assume a consumption value at rest. We have assumed 50W in the table below.

In summary, we can take advantage of real energy consumption data (total kWh consumed by the PC in a whole month) or estimates (the PC works at “X” watts a few hours of the day, and at “Y” watts other few hours).

In addition to this, we are missing a variable, the cost per kWh, that is, the cost of energy. This depends on each household and its electricity tariff.

There are many tariffs with hourly discrimination, where the price is lower at certain times of the day, and even tariffs with variable energy prices, which are very difficult to estimate.

The best thing you can do for the price per kWh is to check the cost breakdown of your electricity bill, and see if it appears. If you don’t know, estimates will also have to be made.

Although in recent years the normal price has been (in United States) around 10 cents/kWh, now almost all tariffs are more than 20 cents/kWh. We can use the $0.20/kWh as a reference.

So let’s do the math. There are two possible ways:

• You have the actual measured kWh value.

Price = Energy Measured × Price Kwh × 1,055

• You have an estimate of daily hours with maximum consumption (HMax in hours, with CMax in kilowatts) and hours with minimum consumption (HMin in hours, with CMin in kilowatts, if they are watts, divide by 1000).

Price = (HMax × CMax + HMin × CMin) × 30 days × 1,055

In USA, we have a 5% VAT and a 0.5% special tax for electricity. That is, 5.5%, so we multiply it by 1,055. The VAT and the special tax that were normally applied in United States were approximately 21% and 5%.

With what we described before, we have made this estimate for different price values ​​($/kWh) and different consumption values.

We have assumed that the computer is used for 5 hours a day at 50W, and for 3 hours a day at the value indicated on the vertical axis.

Rather than illustrating the monthly cost on the electricity bill, the table above illustrates how we can make excessive estimates that are over “alarmist”.

Even when we are playing, the computer does not always have to consume the maximum possible, but on average it will be something much smaller. Hardly any PC consumes 700W on average when gaming, and 300W is much closer to normal.

So, being prudent and reasonable, with 300W and $0.2/kWh as a reference, we could say that a computer consumes about 7 Dollars per month with taxes included. Each one must assess whether it is an excessive contribution to the electricity bill.

How to reduce the Consumption of your PC

After seeing how much my PC consumes, it seemed too much: How can I reduce consumption? There is infinity of routes, some are simpler and others are not. Also, some cost money (buy PC components) and some are free. For example:

• Change your PC’s Power Options and use a saving mode. If it still performs well despite activating it, you can safely leave it on.
• Under Volting your graphics card or processor. This is the hardest thing to do, and should only be done by someone with experience. But it can substantially reduce consumption in gaming computers.
• Simply use the computer less, or avoid leaving it on and shutting it down/suspending it frequently.
• Change the CPU or GPU for a more efficient one. This is only worth something if your PC has very old parts, and sometimes not even that. We do not recommend it because, in addition, it means spending a lot of money. Although if you need to improve performance as well as efficiency, it’s a good idea.
• Buy a more efficient power supply. Unless your source is too bad, the impact on consumption will be very small. Of course, check that your source has an 80 plus certificate.

In short, knowing how much a computer consumes is not a very complex process, but there are too many variables to consider if we want to correctly calculate its impact on the electricity bill.

As we say, the best thing is to buy a consumption meter and measure the energy consumption for a while, knowing the real one.

Even so, if we use our estimates as a base, we could say that most gaming PCs represent a monthly energy cost of less than 10 Dollars, and it is normal for them to be less than 5.

How much does your computer consume? Have you already done the calculations? Do you think your PC has too much impact on your electricity bill? Do not hesitate to leave your comments!