Is It Bad For A CPU To Run At 100% Usage?

A CPU is one of the most critical and expensive components that go into your computer, so you’ll want to pay extra attention to it working as advertised. But what exactly does this mean? For instance, is running a processor at 100% of its capacity okay?

It is alright for a CPU to run at 100% usage for the brief moments when it hits its highest processing loads. However, constantly running at peak capacity or consistently hitting performance thresholds may indicate inefficient resource allocation, an underpowered machine, or risks of heat damage.

How To Fix High CPU Usage

While CPUs are built to work at full capacity, pushing them to their limits for extended periods is not recommended.

Not only can high CPU usage pose threats to its lifespan, but it can also indicate underlying problems. So, it’s essential to keep the usage down to a safe threshold by trying the following: 

1. Reboot Your Computer

Every time your computer boots, it purges temporary files. So, if your CPU is maxed out because of a build-up of temporary files, rebooting your machine may be enough to restore it to an efficient state. 

Once you restart, check to see if CPU usage reverts to normal. On Windows, you can do so by opening the Task Manager (CTRL + ALT + DEL). On Mac, open the Activity Monitor (Command + Shift + U).

If the CPU usage has fallen to the normal figures, your problem has been solved, and you do not need to proceed any further. If not, keep going.

2. Close Any Unnecessary Applications That Are Running

While most modern processors can handle a degree of multitasking, there are limits to these capabilities.

Moreover, the more affordable the processor, the more modest its multi-tasking capability is likely to be.

Closing any unnecessary applications can free up valuable computational resources that can be better redirected.

If your processor is still running at elevated levels of usage once you’ve closed all the open apps, other tasks may be running in the background and hogging its resources. You’ll need to find these and close them, too.

To find out which programs are running at any given point in time, open Task Manager on a Windows computer and Activity Monitor on an Apple machine.

In both instances, you’ll see a list of all the open applications and details on how much processing power each is using.

Scrutinize the list for:

  • Background processes that aren’t urgent, including updates and installations in progress.
  • Operating system processes that are draining your CPU.

If you are unsure what a particular process does, look it up before closing it. Many background processes are essential to the smooth functioning of your operating system.

Turning them off can cause problems elsewhere, so proceed with caution.

Check if CPU usage has normalized once you’ve closed all the processes you do not need. 

3. Update Your Software and Drivers

Update concept art for computers.

When performing the previous step, you might have noticed some applications taking up inordinate amounts of processing power.

If that’s the case, updating and reinstalling these applications might help.

If you encounter any programs that won’t close, refer to my article that shows you how to force quit on Windows.

Newer versions will likely be lighter and more compatible with the newest hardware. So updating any outdated software will free up CPU resources and help your computer run faster.

While you are at it, updating the drivers might also be a good idea. 

All the hardware components in your machine have corresponding drivers. This includes your motherboard, graphics and audio cards, printers and scanners, and any input devices you use, such as mice, keyboards, and controllers.

When downloading drivers, look to the original manufacturer’s sites and avoid downloading any files from third-party providers.

Many sites put out old and outdated drivers; in the worst cases, you may even end up downloading and installing malware. 

If you want to be completely thorough, update your system’s BIOS to the latest version.

Once again, look up your motherboard manufacturer’s website and only download the driver for your specific model.

Note that updating a BIOS usually doesn’t improve a computer’s performance. It can also create new issues if done improperly. So, only attempt this if none of the earlier steps have resolved the issue. 

4. Scan for Viruses and Malware

Computer virus concept art.

Viruses and malware are increasingly common these days. If your computer is infected, it could easily explain the sudden spikes in CPU usage you’re noticing. 

Some viruses plant adware on your computer. They continue to produce pop-up ads bombarding you with unwanted information. 

Others may be more stealthy. For instance, cryptocurrency miners may use your computational resources to mine Bitcoin without your knowledge.

If this is happening, not only are your CPU resources being used for someone else’s benefit, they’re being redirected away from tasks essential to you.

Malicious programs can also camouflage themselves by using names resembling other genuine software installed on your machine, so keep an eye out for familiar-sounding names that have minor misspellings or naming differences.

You’ll want to run a thorough antivirus scan to ensure you do not have any such programs running on your computer

5. Restore Your Operating System to an Earlier Recovery Point

If you’ve had your computer for a while and it has been working well until recently, you can try restoring your operating system to the most recent prior state when everything worked correctly. 

Of course, you must set up restore points on your machine in advance for this method to work. You will lose any files created in the interim should you proceed. 

However, the beauty of this solution is that it works even if you cannot precisely locate the source of the problem. 

On Windows systems, you can perform a system restore by following these steps:

  1. Click on the Windows icon in the bottom-left-hand corner of your desktop screen and type Control Panel.
  2. In the Control Panel search box, look up Recovery.
  3. Click on Recovery, followed by Open System Restore.
  4. In the Restore System Files and Settings window, click on Next.
  5. You will be shown the saved recovery points.
  6. Choose the most recent recovery point when everything worked well.
  7. Start the system restore and wait while the computer makes the necessary changes.

Follow these steps to restore a Mac:

  1. Restart your computer by holding down the power button and keeping it pressed.
  2. Keep holding down the button even when text information tells you that if you continue holding down the power button, you can access startup options.
  3. Select Options followed by Continue.
  4. Once the Recovery dialogue opens, select a restore point and begin the recovery.

6. Clean Your Computer and the Check Thermal Paste

If your computer cabinet and its fans have accumulated a lot of dust over the years, this can cause CPU temperatures to rise and force throttling to prevent heat damage.

Cleaning up your computer case can help your fans work effectively and restore CPU functioning to normal. 

If that doesn’t work, ensure you have an effective cooling system. Perhaps the fans installed are inadequate for your computer’s processing demands.

Remember to turn off your device and unplug all attached peripherals before proceeding. Otherwise, you may damage the electrical components inside from a static discharge.

You may also need specialized tools like compressed air to dislodge stubborn dirt.

Pay careful attention to the CPU cooler not only to ensure it is clean but that it is also mounted properly.

And, of course, replacing any aged thermal paste. If the thermal paste hasn’t been replaced in two years or more, consider a fresh application to ensure the coolers can do their job.

7. Reinstall Your Operating System

A final step you can take is to reinstall your operating system. Unfortunately, you will lose all your data and any installed applications and preferences that are not saved elsewhere or on the cloud.

So, understandably, this is a last resort and not something to rush into.

Normal CPU Usage Ranges

Like most computer users, you probably use your computer for many tasks.

You might check your mail in the morning, join a team meeting post-noon, and play multiplayer games after dinner, all on the same day. 

Not all of these computational tasks require the same amount of processing resources. So, chip manufacturers have designed their products to deliver only as much computational power as needed.

This saves energy and prevents chips from overheating.

For the same reasons, your processor usage varies depending on the tasks you throw at it. So, a well-functioning computer’s processor usage should look something like this:

  • On idle: If your computer is on, it will use some processor resources (1-5%) to perform background tasks, even if you have no open applications.  
  • Browsing, streaming, and light activity: Tasks that are not demanding, such as browsing websites or streaming videos, will not stress your processor too much (5-20%).
  • Processor-intensive tasks: Even the most processor-intensive tasks should only push your processor to 50-80% of its capacity, as long as adequate cooling is in place. Gaming, 3D graphics editing, modeling and simulations, and video editing fall into the heavy processing category.
  • Booting, loading applications, and highest processing demand tasks: Only a few minutes should your processor hit peak performance loads (80-100%). This might happen when your computer boots, loads heavy applications, or perform the most processor-intensive tasks within the most demanding applications. Playing games at their highest settings or rendering out high-resolution videos are among these demanding tasks.

Why Consistently High CPU Usage Can Spell Bad News

For a range of interrelated reasons, consistently high CPU usage can disrupt your machine’s smooth functioning.

If your processor is running at above 80% consistently or is showing elevated usage even when you aren’t throwing much at it, you might have a problem on your hands. Here’s what could happen:

You Have Hit Your Upward Performance Limits

While it might seem obvious, it is worth reiterating that when a CPU hits 100%, it can go no further. No more computational tasks can be transferred to the processor at this point. 

Further, even ongoing tasks will be slowed down as different tasks queue for resources. Applications may freeze or crash, causing you to lose unsaved data and waste valuable time.

A CPU running at 100% indicates you have reached the upper limits of performance. You need to sort out something in your software environment, stop using certain applications, or upgrade to a more powerful chip.

Your System May Be Underperforming

If you’ve already installed a high-end processor, it can be frustrating to see it hit its performance thresholds, especially when you haven’t pushed your machine aggressively. In this case, you may wonder whether you haven’t given your processor the right software environment to shine. 

An individual application may be placing an unusually heavy processing burden on your machine and slowing it down. If this application is essential, it might suggest your processor is underpowered for your needs.

Your CPU Faces the Risk of Heat Damage

Finally, a CPU running at 100% consistently is exposed to high amounts of heat. That’s why processor manufacturers limit the draw on CPU resources to prevent their chips from overheating. 

While a CPU running at 100% is running within its intended range of performance, it will need excellent cooling to keep it functioning efficiently and protect it from heat damage. So, if your processor usage has suddenly spiked, it could indicate a problem with its cooling infrastructure.

Even with the most efficient cooling system installed, there is a risk of heat prematurely curtailing its lifespan. You’ll want to get your processor’s usage numbers down urgently to prevent this from happening.

Please refer to my article about how to see if a CPU has been damaged from heat if you want to know more.