Understanding CPU Usage: An Ultimate Guide
We dive into the nitty-gritty of how to tell if your CPU needs adjustment, plus critical tips to optimize its performance.Buying Guides

It might be hard to imagine that a device that can process millions of instructions per second would ever run out of capacity. And yet, a computer’s central processing unit (CPU) definitely isn’t infinite! The CPU is the brain of your computer — and just like a human brain, it can become overloaded with too many commands and calculations.
Add up the processing power that your CPU uses for all of its tasks at any given time, and you’ll have what computer geeks know as the CPU usage or CPU load. This is expressed as a percentage, measured against the processor’s capacity — so a CPU usage of 30 percent is smooth sailing, while 90 percent might get you worried.
But should you be worried about a high CPU load? Moreover, what can you do to bring it down if it’s too high? Up ahead, we’ll dive into the nitty-gritty of how to tell if your CPU needs adjustment, plus critical tips to optimize its performance.
How to See Your CPU Usage
Before we start troubleshooting, the first step is always to investigate the current state of your CPU load. To do this, you’ll want to find your computer’s CPU management utility. Here’s how to see your CPU usage, depending on which operating system you’re using:

Windows 10/Windows 11
Press CTRL + SHIFT + ESC to access Windows Task Manager. This do-it-all utility offers several tabs with different information, but the first one you’ll see is Processes. Here, you’ll find every process and application currently running on your computer, as well as the amount of CPU power, RAM, and other computing resources that each one uses. In addition, you can use End Task here to close misbehaving applications.
Another key tool in Task Manager is the Performance tab, which provides a real-time graph of CPU usage. You can make monitoring more convenient by right-clicking the CPU header on the left side and choosing Summary View for a slimmed-down widget that tracks CPU and other system resources. Want to get the nerdy details on which cores your processor is using? Right-click the graph and choose Change graph to > Logical processors to see a full breakdown.
macOS
Access the Activity Monitor application from Spotlight search or Applications > Utilities. Activity Monitor offers a list of currently running apps and processes, including the percentage of CPU power each one is currently using and other potentially useful info. You’ll also find a Stop button that allows you to end tasks.
The CPU usage graph at the bottom of the Activity Monitor window provides a real-time readout of your utilization, including how much is allocated to both system and user processes. If you’d like to get a little more granular, double-click the graph to see a core-by-core summary. It’s also easy to keep an eye on your Mac’s CPU usage while you’re focusing on other tasks. Just choose View > Dock Icon from the menu bar to see a graph in your dock.
Is High CPU Usage Bad?
Not always, but it can be! First, know that it’s totally normal to see your CPU usage spike into the neighborhood of 80 or even 90 percent while you’re doing things like gaming, editing videos, or using audio production plugins. However, the higher your CPU usage gets, and the longer it stays there, the more you should pay attention to what’s causing it.
That’s because sometimes a high CPU load can harm your performance and/or indicate that there’s something wrong. If you find yourself with high CPU usage in either of the following situations, it’s probably time for some troubleshooting:

Your CPU temperatures are causing thermal throttling.
CPUs under high load produce more heat. If the heat goes above safe levels (generally starting at around 85º to 90ºC), your PC will start to throttle the processor’s speed to control the heat and protect your components — good for your PC, bad for performance.
If you’re experiencing poor performance and/or high CPU usage, it’s worth checking on your CPU temperatures. Tons of free utilities are available that allow you to check your CPU’s temperature, including many that you can run as an overlay window while you’re gaming to watch your temps in real-time. (Core Temp is a popular and free option.)
High CPU temperatures and thermal throttling mean something is working your CPU too hard and getting it too hot. That might mean your computer is dusty, or your CPU can’t keep up with its tasks. Either way, you’ll want to do a little investigation.
There’s no obvious reason for your CPU load to be so high.
Sometimes, your CPU load might be unusually high when your computer is idling, or when it’s using an application that should be trivially easy for its specs. This can be an indicator that something is happening you should be aware of, so hop over to Task Manager or Activity Monitor and take a look at your currently active processes.
Several different things can cause anomalously high CPU loads. It might be as simple as a Windows process that’s stuck in a loop or a misconfigured setting on your computer. On the other hand, it could also be a cybersecurity threat like viruses or malware. Regardless of the cause, the steps we’ll talk about next will help you locate and solve the problem.

Tips for Lowering CPU Usage
1. Reboot Your Computer
Yes, it could literally be that easy! Rebooting your computer via the Restart option should be your go-to option pretty much any time your machine is doing something you don’t like, and that can include all kinds of CPU-related issues. It’s the computer equivalent of a shower and a good night’s sleep: It won’t fix everything, but it’s a good place to start.
2. Update OS, Drivers, and Software
Here’s another classic piece of IT help desk advice: Make sure everything is updated. That includes your operating system, hardware drivers for components such as your GPU, and any software you’re using. Keeping everything patched and updated helps protect against software glitches that can eat up processing power, and it’s also a critical part of keeping your system secure.
3. Close Programs and Processes
If your computer is fully updated and rebooted, it’s time to start investigating what’s actually using up your CPU power. Take a look at your CPU management utility and note how much CPU power your computer is using to run its various applications. (You might be surprised to find that even an everyday application like Google Chrome can eat up a surprising amount of CPU.)
Once you’ve discovered what’s using up so much power, you can close it — so long as you know what it does. Pop the name of anything you don’t recognize into a search engine before you close it, so you don’t accidentally stop any critical processes. System processes should be left alone more often than not, but this is an easy way to realize that (for example) you left a streaming app running by accident.

4. Check Settings and Configurations
Next, see if there are any settings or hardware configurations you can change. These will depend heavily on your individual system build and operating system.
- Graphics Card Port: If you have a graphics card, check to make sure your monitor’s HDMI or DisplayPort input is connected to the card rather than your motherboard. If it’s plugged into the motherboard, your system might be using the much slower GPU built into your CPU, which can cause your CPU to go crazy trying to keep up.
- Usage Limits: Windows offers various tools that allow you to cap how much CPU certain applications use. Changing the process priority and CPU affinity are two potential solutions for taming memory-hog applications.
- Hardware Acceleration: Graphics card owners should also check the settings of any CPU-intensive applications to see if they offer hardware acceleration. This option sends some processing tasks to the GPU to make things a little easier on the CPU.
5. Make sure your PC is clean and has good airflow.
Dust, dirt, and debris can choke your PC’s performance by preventing the CPU from effectively getting rid of heat. So, if you’re struggling with high CPU loads, try opening up your PC and looking for gunk, especially in areas like the fans, vents, and heatsinks.
Cleaning a PC case isn’t too difficult. A can of compressed air, a small soft brush, and a lint-free cloth are all you need. (We hope we don’t have to say this, but stay away from liquid cleaners.) Laptops require a little more care, and notebooks with a sealed body design (such as MacBooks) generally shouldn’t be opened except by an authorized repair person.
It’s also possible that your computer is in a position that restricts its airflow. This is especially common with laptops when they sit on top of a pillow or blanket, but it can happen to desktops too, if they’re placed directly against a wall or in an otherwise unventilated space. For the best cooling performance, your computer should always be on a flat surface, with nothing blocking its exhaust vents.

6. Scan for Viruses and Malware
Viruses and other malware can hijack your CPU for all kinds of nefarious purposes — from serving you spammy ads to mining crypto for cybercriminals. What’s more, many of these programs are built to hide themselves from basic utilities like Windows Task Manager. If your idling CPU usage is way over the top consistently and your system utilities aren’t showing you an obvious cause, there’s a chance that your PC might have picked up a virus or another type of malware.
Modern editions of Windows and macOS both have robust built-in features to protect from online threats, but they’re not perfect, and supplemental protection is always a good idea. Our recommendation: Download a reputable free anti-malware utility and use it to scan your computer. (Take care with what you download, as many no-name free antivirus programs might as well be malware themselves.)
7. Determine If Your CPU Is Bottlenecking
If you’re using a graphics card, the CPU’s load can max out quickly if it renders frames faster than the CPU can send them. (Picture the GPU as a dog that returns the ball dozens or hundreds of times per second and the CPU as the human struggling to throw it fast enough.) This is what hardware nerds know as a “bottleneck”: when one component can’t keep up with the increased performance of other system elements.
Bottlenecks are especially common in PCs with older processors and newer graphics cards. To find out if you’re experiencing one, pull up a hardware performance utility (HWMonitor and MSI Afterburner are two popular free choices) and watch the CPU and GPU usage while doing something demanding like playing a game.
The key sign to look for is CPU usage that’s significantly higher than GPU usage, which generally means the GPU is outpacing the CPU. In that case, you’ve got two basic options: overclock your CPU or upgrade it. (Unfortunately, both of the following options are PC-only and will not work on a Mac.)
8. Overclock Your CPU
If your CPU is an “unlocked” model, you can overclock it to run it faster than its factory settings. This can potentially reduce your CPU load, depending on what your processor can handle. Generally, you’ll use an overclocking tool such as MSI Afterburner to do this — but read up on overclocking before you try it.
That’s because, although overclocking won’t destroy your PC unless taken to extremes, it can reduce your processor's overall stability and lifespan. It can also get a little complex and involves tinkering with components that many PC users simply don’t want to touch, so it’s generally not something that PC novices attempt. That said, if you have a little tech knowledge and are ready to jump into the world of overclocking, it can help you squeeze some more life out of an older processor.

9. Upgrade Your CPU
While you shouldn’t jump to this immediately, sometimes the hard truth is that your CPU isn’t up to the tasks you need it for. It may be time to upgrade if your PC has an older or budget-model processor that’s no longer cutting it.
This will require a little bit of research. For one thing, you’ll need to find a CPU that’s compatible with your motherboard’s socket type and chipset. (Many PC users purchase a motherboard/CPU combo to save themselves the headache, although this means switching out your motherboard.) Beyond that, get familiar with the most important CPU specs. Clock speed is especially relevant for gamers, while number of cores should be a priority for applications such as CAD and rendering video.
Have you been overclocking your brain dealing with CPU issues? Let Micro Center’s PC professionals help. Our associates will perform a full-service computer diagnostic on your machine, with same-day service available when you bring in your PC at least four hours before closing. Looking for a new processor? We have a full range of CPUs at all price and performance levels — or use our custom PC builder tool to create a high-performance new system from the ground up.