Why does Avast use so much CPU?

Ever wondered why your PC slows down when you install Avast? It is not because it’s overprotective. There are many reasons for Avast using so much of your computer’s resources, but we will try to explain the most common ones.

First of all, antivirus programs use many system resources to scan and analyze files on your computer to find out whether they are malicious or contain malware. If they do, then the software can remove them before any damage is done.

This process usually takes up more than half of the CPU power on your machine, which might affect other applications that you’re running at the same time – especially if there’s an ongoing virus attack going on. 

But don’t worry! We have some tips and tricks so that you can keep using Avast without slowing down your computer.

Read more: Avast VPN review – Pros and Cons using Avast

More CPU for antivirus

The CPUs are not powerful enough?

If you are using a single-core CPU, it might not keep up with your PC encounters’ number of processes. By installing the Avast software on a multi-core system, we can process all data in parallel, thus eliminating possible future problems.

Many PCs are still using 32 bit CPUs instead of 64 bit CPUs because they are less expensive and sufficient for standard computer uses. However, if your computer runs a 64-bit version of Windows or Mac OS X, you should deal with all the challenges by upgrading to a 64-bit operating system. It will boost performance when handling complex applications like the Avast antivirus software.

The minimum processor needed for using Avast 2021 is Intel Core i3. Still, if you have a computer with the latest processors and other software that requires many resources, it is recommended to use an Intel Core i5.

If you don’t know whether your CPU is 64 bit, there are many ways to find out. You can download and run the checker on this website. Or go to Start/Control Panel/System and Security (or System & Security in Win7) and click “Advanced system settings” – if it’s 64 bit, it will say so underneath System type.

The other suggestion is to install a simple network monitoring software like Little Snitch for Mac or Bandwidth Monitor for Windows that will display all incoming connections. Once you have installed the Avast antivirus software, these add-ons will monitor every traffic that goes through your computer – including what applications use them. When something suspicious happens with your Internet connection, the monitoring software will see it and notify you.

More resources for an antivirus

You need more RAM, maybe?

If your computer has a limited amount of RAM (memory), then Windows can only store some of the information in this memory area. The rest of the data is stored on your hard drive, which uses up disk space to lose gigabytes of storage.

With more RAM, however, you can run more applications at one time without affecting performance because they are loaded into memory rather than frequently having to swap between the two areas.

The simplest way to check how much RAM your machine has is to look for it under My Computer/This PC: Right-click and go to Properties; click on Memory in System Information window that opens up; the amount of RAM you have will usually be in the first line.

If your computer has at least 2 GB of RAM, then you can run Avast safely without significant problems. But if it’s less than that – 1GB, for example – then we suggest adding more memory because the system won’t allocate its resources efficiently. 

Adding a couple of gigabytes should help avoid lagging and freezing. It’s best to get high-quality DDR3 modules with heat sinks or fans because they are designed to overclocking and achieve maximum performance.

More memory for an antivirus

Do you need a faster HDD (an SSD, maybe)?

HDDs with a sustained read/write speed of 10 MB per second or above are good enough to install the Avast software and allow the system to run smoothly. If, however, you want your computer to perform at peak levels and don’t mind spending a few extra dollars, then put in an SSD instead.

Windows features several built-in apps that can help free up space, but it’s often necessary to deactivate certain applications and reset the computer. A memory cleaner like CCleaner or Windows 10 MRU Cleaner can identify which programs are unnecessary for running Windows OS and release some extra RAM – freeing up more storage capacity than just deleting an app completely from your PC would do.

Apps like Memory cleaners make identifying unused software simple. Hence, you know what is taking up valuable resources on your device without having to go through every program one by one (which could be tedious). The benefits don’t stop there! Once you’ve identified these unwanted programs, they’re easily removed by clicking delete

You could also consider getting a new graphics card and monitor – if they’re too old, they may affect performance when installing large pieces of software.

Do you need an ssd or more hdd space

Do you need more free disk space?

Go to My Computer/This PC and check the disk space. If you’re low on space, then delete some of your old files and temporary internet files or add more disk space by connecting an external HDD and transferring big or unused files to it.

To speed up your computer, you can disable all programs that start at Windows load. To do this, go into Control Panel > Programs and Features by selecting Avast from the list (remove any other antivirus software in use before proceeding), then click the Remove button.

If you uninstall Avast from Control Panel->Programs->Programs->Features menu, keep in mind to restart your computer afterwards for changes made the system comes into force.

The last tip is not only for improving performance but also for security purposes. If you’re not sure whether having an application or service installed in your system is beneficial to you but think it might be, then consider deleting it. Most programs don’t provide any significant value and are just a waste of resources.

An old computer will run much slower than a new one, so there’s no point blaming Avast for it – its speed has more to do with the components: processor (dual-core processor), RAM, HDD, graphics card and monitor.

If you have doubts about the performance of your PC, try using SSD with less capacity (120 GB) instead of the larger ones. This way, you’ll find out what kind of impact this type of storage device yields when working with the Windows operating system.

Hopefully, all this information will help you solve the problem of Avast being too slow. If you have other suggestions, please let us know in the comments, and we will be glad to include them in our article! 

Avast is a good Antivirus


Avast is a good antivirus, but sometimes it can be a bit overprotective. It’s like the dad who always has to know where his daughter is and when she’ll get home. 

It scans for everything on your computer because it doesn’t want you thinking you’re invincible online. So, if Avast detects something new that it hasn’t seen before or an old friend that should have been deleted years ago – let’s say the CPU usage will increase dramatically.

We mentioned a few of the most common reasons for Avast using up your CPU. If you follow the given tips and tricks, you won’t have to wait long before your computer starts functioning at its total capacity.