Fix: SysMain High CPU And Memory Usage In Windows 10 & 11

Is the SysMain process taking up much CPU and RAM? Here's how to fix SysMain high CPU and memory usage in Windows 10 and 11.

Monitoring active processes and the number of system resources they consume is normal for most PC users. Realizing one of them takes up more than half of all available computing power, however, isn’t.  

The SysMain process is well-known for this. It occasionally utilizes excessive CPU and RAM, making Windows users question if it’s potentially harmful.

Unfortunately, due to the complexity of the Windows OS and the wide variety of processes associated with it, forcefully closing one from the list often seems like a risky move to users. The alternative though is allowing the process to consume more than half of your PC’s resources, making it practically unusable.

So, what’s the solution?

Keep on reading to find out.

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What Is The SysMain Process, And Why Is It Running On My PC?


The developers of Windows aim to make the operating system run as smoothly as possible and provide their users with a good experience using it. This requires a lot of optimization and implementation of features that speed things up for the person using the computer.

One of those features is “SuperFetch,” or as most users know it, now after Windows 10 was released, SysMain.

In simple terms, SysMain is an optional Windows process designed to speed up the user’s workflow by “remembering” their most-accessed files and programs, then “fetching” that information and storing it in the RAM and HDD/SSD cache. The next time the user needs access to those files and programs, they should load much quicker due to this feature.

SysMain is not a critical Windows process, and you can disable it without the operating system becoming unresponsive or sending a warning message. In simpler terms, you can disable SysMain without worrying “it’ll break something” on your computer.

SysMain is not a virus or a process that damages your computer in any manner, despite its reputation for utilizing substantial resources when running behind the scenes.

Most users that experimented with SysMain reported that the difference it makes in terms of speeding up tasks is unrecognizable, but disabling it yields visible performance benefits due to the reduced CPU and RAM resources consumed.

On older systems, almost all users reported that it causes notable slowdowns. Those with high-end performance computers reported no visible benefits of enabling it, yet could feel a “performance hit.” 

With that said, it’s up to the user to decide whether to keep SysMain enabled or shut it off, but based on our and many other users’ experiences, it’s preferable to turn it off, especially if it’s already causing problems.

And one more important thing to note.

SSDs (Solid State Drives), commonly seen as the norm in current computers, have a restricted lifespan shown as cycles. That being said, individuals who wish to extend their SSD’s lifespan deactivate SysMain to avoid ongoing background checks that use up cycles.

In addition, since most users have an SSD and hard drives are seldom used anymore, the substantial speed difference between SSDs compared to HDDs already makes the SuperFetch or SysMain obsolete.

In some cases, even Windows automatically disables the SysMain process if the user has Windows installed on an SSD.

Shutting/Disabling The SysMain Process


Now that you know more about SysMain and what it does, you can decide whether to disable it or leave it on.

If you choose to disable it, here are some of the methods to do that:

Through The Services Panel

  1. Simultaneously press the Windows + R buttons on your keyboard to open the Windows Run utility. In it, type in services.msc and press Enter on your keyboard to initiate the search.
    Windows services.msc
  2. Click on any service, then press the S button on your keyboard to skip to the services starting with that letter.
  3. Locate the SysMain service and right-click it with your mouse. Choose Stop.
    Windows SysMain Stop
  4. Right-click it again and choose Properties. In the “Startup type:” section, change its status to Disabled. Press Apply and then OK to save the changes.
    Windows Startup type Disabled

Now restart your computer, and you’ll notice that SysMain no longer starts automatically when your system boots up.   

Through The Registry Editor

  1. Simultaneously press the Windows + R keys on your keyboard to bring up the Windows Run Utility. When it opens, type in regedit and press Enter on your keyboard to initiate the command.
    Windows RegEdit
  2. Paste the following key: “HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesSysMain” into the address bar and press Enter to make the navigation faster and easier.
    Windows Registry Editor SysMain
  3. Right-click the Start value, then choose Modify from the list of options, as shown in the image below.
    Windows Registry Editor Modify
  4. In the “Value data:” field, change the number to 4, and make sure Hexadecimal is selected under “Base” on the right side. When done, press OK to save the changes.
    Windows Registry Editor Value data
  5. Exit the Registry Editor and Restart your PC.

Using Command Prompt

  1. Press Windows + R simultaneously on your keyboard to open the Windows Run Utility. In it, type in cmd, then press CTRL + SHIFT + ENTER to open a Command Prompt window with administrator privileges.
    Windows Command Prompt
  2. Copy and paste the following command: “sc stop “SysMain” & sc config “SysMain” start=disabled” in the Command Prompt window, then press Enter on your keyboard to initiate it.
    Windows SysMain Command Prompt
  3. Restart your computer for the changes to take effect.

That’s all there’s to it!

After this change, SysMain will no longer run in the background when your computer boots up.  


Now you comprehend more about the SysMain Windows process, what it does, and why users frequently choose to disable it.

Although this is not a critical Windows process, on some systems, it runs automatically on startup, causing slowdowns and using too many processing resources.

Luckily, you can disable it and hopefully improve your computer’s performance using one of the methods listed in this guide.

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Bojan Veselinovikj

Bojan is a video-game developer and a tech enthusiast. Combining these two passions allow him to keep you informed on everything that's new in this fast-paced digital world.