How to Fix Performance Issues on a Windows PC

Authored by: Support.com Tech Pro Team

1. Introduction

Diagnosing performance issues on Windows 10 can be difficult. This guide will take you, step by step, through Microsoft-recommended checks and fixes to help make sure your computer is performing as best it can.

2. Check for Updates

  1. Open the Start menu and select Settings.
Windows 10 Start Menu

Windows 10 Settings
  1. Select Update and Security.
Updates and Security Settings
  1. Select Windows Update on the left, then select Check for updates.
Update and Security with Windows Update and Check for updates highlighted.
  1. Once the system has finished checking for updates, it will automatically download and install the latest applicable updates.
  2. The system also may prompt you to restart, if it does, please do so at your earliest convenience, otherwise the update process will not complete.If you system was already recently updated, chances are that no further updates are available and your Update status will indicate: Your device is up to date.

3. Disk Cleanup

Windows needs about 2 GB free space, at minimum, to function. In order to properly update and perform other functions, around 5 GB free space is recommended.

A simple way to help free up space is to remove temporary files; files that were useful during an update or other working of the computer, but now simply take up space.

This will guide you through safely clearing those temporary files.

  1. Open the Start menu and select Settings.
Windows 10 Start Menu

Windows 10 Settings
  1. Select System.
System Settings
  1. Select Storage on the left, then select Temporary files on the right.
System Settings with Storage and Temporary files highlighted.
  1. Place a checkmark next to each item, then select Remove files.
Temporary files settings with each item checked and remove files highlighted.

4. Uninstall an App

You may need to remove an app because you need the space or simply don't need it anymore. The following steps show you how to easily remove an app.

  1. Click Start then Settings.
Windows start menu with the start button and settings highlighted.
  1. Next, Select Apps.
Windows Settings with Apps highlighted.
  1. Scroll down and locate the app you wish to remove, and click on Uninstall.
Apps screen with the uninstall option for an app highlighted.
  1. Carefully read any prompts in case there are special instructions. Proceed until the application is removed.
  2. Some applications may require that you reboot.

5. Restart Your PC

Before your restart or shut down your PC, make sure to save all necessary work to prevent data loss.

  • Using the Mouse
  • Select the Start menu.
Windows 10 Start button

  • By default it is in the lower left corner of your screen.
  • Select Power, then select Restart.
Start menu with Power and Restart highlighted.
  • Using the Keyboard
  • Press the Windows and X keys at the same time. This minimizes any open windows you may have.
Keyboard with Windows and X keys highlighted.
  • Press the Alt and F4 keys at the same time. This tells Windows to close the desktop.
Keyboard with Alt and F4 keys highlighted.
  • Select Restart, then OK.
Shut Down dialog with Restart and OK highlighted.

6. Check Memory Usage

Your computer's performance can suffer if it is facing limitations caused by system memory (or RAM). Checking how much memory your computer has physically installed, and how much of that memory your system is using will help diagnose a potential memory issue that is affecting your system's performance.

  • In general, Windows 10 requires 2 GB of memory to work, but performance and stability will be limited. Windows 10 runs better with 4 GB. If you use a lot of programs at the same time, or very large programs (such as games), you may require more memory, such as 6 GB or 8 GB or more.
  • You can choose to use fewer programs, or add more memory to your computer if you find yourself regularly using up all available memory.
  1. Press the CTRL + ALT + DEL keys on your keyboard at the same time.
PC Desktop Keyboard with Ctrl-Alt-Del highlighted.
  1. Select Task Manager.
GINA screen with Task Manager highlighted.
  1. Select More Details at the bottom.
Task Manager with More Details highlighted.
  1. Select the Performance tab at the top, then select Memory on the left.
Task Manager with Performance and Memory highlighted.
  1. Look at the amount of memory you have on your computer, and how much is in use.
Task Manager Memory with Total Memory and Memory In Use highlighted.
  1. Total Memory
  2. In the top-right corner, you'll see how much memory is physically installed in your computer.
  3. Memory In Use
  4. In the list at the bottom, you'll see how much is in use by Windows, and the programs you have open.
  5. In general, you want 1GB to 2GB available while you have most of your regular programs open.

You can check this information when you have your normal programs open. Open a few programs you usually use, and return to this window. See if you're using more memory than you have; this indicates Windows is using some of your hard drive space as memory, which is very slow.

This is a physical part of your computer, not something you can download or modify through software. If you want to add more memory to your computer, contact the company you purchased your computer from, or a local technical support service.

Virtual Memory or Your Paging File

The paging file is a hidden file on your computer's hard drive that Windows 10 uses as memory, and acts as an overflow of the system memory that holds the data needed for applications currently running on your computer. Increasing the size of your paging file can help with speed issues.

  1. In the search bar, type "Control Panel" and select it.
Windows 10 Search with control panel selected
  1. Select System and Security.
System and security selection
  1. Select System.
The system panel
  1. Select Advanced System Settings.
Advanced system settings link
  1. Under the Advanced panel select Settings within Performance.
Advanced panel showing performance settings
  1. Select the Advanced tab and under Virtual Memory select Change.
Performance options
  1. To set your own Paging File size, clear the automatically manage paging file size for all drives selection.
Automatically managed page file
  1. Select Custom Size to set your own Virtual Memory limits. Click Set to finalize your sizes.
Setting your paging file
  1. The minimum size of the Page file can be up to 1.5 times the amount of physical memory (RAM) you have installed. The maximum size can be 4 times the amount of the physical memory. For example, if your computer has 1GB of RAM, the minimum Page file size can be 1.5GB, and the maximum size of the file can be 4GB.

7. System Restore

Turning the system off while System Restore is running can cause corruption. If your device is battery-operated, connect it to a power outlet first as System Restore may take time and should not be interrupted.

System restore will remove any programs installed and settings made after the selected date.

  1. Open the Start Menu, type "rstrui" in the search box and then click rstrui.
Windows 10 search box results.
  1. System Restore will open. Click Next.
Windows 10 system restore interface.
  1. Select a date before the issue started, you may see more than 1 restore point. Click Next afterwards.
Windows 10 list of available restore points.
  1. Confirm your restore point by clicking Finish. Click Back if you wish to change the restore point.
Windows 10 confirm system restore options.
  1. The process will take some time to finish. The system will also reboot shortly.

8. Startup Check

After checking on what your computer is doing during normal use, you may have spotted some things actively running that you don't use or need running 100% of the time. Most times, programs are set to be launched and run as soon as your machine boots up. This process will help you disable unnecessary programs from starting up with your computer.

  1. Press the CTRL + ALT + DEL keys on your keyboard at the same time.
PC Desktop Keyboard with Ctrl-Alt-Del highlighted.
  1. Select Task Manager.
GINA screen with Task Manager highlighted.
  1. Select More Details at the bottom.
Task Manager with More Details highlighted.
  1. Select the Startup tab at the top.
Task Manager with Startup tab highlighted.
  1. Look carefully through this list. If you see an item you do not want to startup whenever you turn on your computer, highlight it, and choose Disable at the bottom.
Task Manager Startup with application and Disable button highlighted.

9. Restart Your PC

Before your restart or shut down your PC, make sure to save all necessary work to prevent data loss.

  • Using the Mouse
  • Select the Start menu.
Windows 10 Start button

  • By default it is in the lower left corner of your screen.
  • Select Power, then select Restart.
Start menu with Power and Restart highlighted.
  • Using the Keyboard
  • Press the Windows and X keys at the same time. This minimizes any open windows you may have.
Keyboard with Windows and X keys highlighted.
  • Press the Alt and F4 keys at the same time. This tells Windows to close the desktop.
Keyboard with Alt and F4 keys highlighted.
  • Select Restart, then OK.
Shut Down dialog with Restart and OK highlighted.

10. Repair Windows Image (DISM)

Make sure you are connected to the Internet before beginning these steps.

  1. Choose the Start menu, and type PowerShell into the search.
start menu with PowerShell search
  1. Using your right mouse button, right click on PowerShell in the list above. A special menu will open. Choose Run as Administrator.
Right click menu for PowerShell with Run as Administrator highlighted
  1. Windows will ask if PowerShell may make changes, click Yes.
User account control prompt with yes highlighted
  1. At the prompt, enter the following command, then press enter on your keyboard:
  2. dism.exe /Online /Cleanup-image /Restorehealth
PowerShell with dsim command entered
  1. Windows will automatically go through every system file, make sure they are valid, and replace any corrupted files.
dsim running in PowerShell

11. Adjust For Best Performance

  1. Select the Start menu, search for Performance. Then, select Adjust the appearance and performance of Windows from the menu.
start menu with search for performance and adjust performance choice highlighted
  1. Select Adjust for best performance at the top, then click OK at the bottom.
Performance options with adjust for best performance highlighted

12. Restart Your PC

Before your restart or shut down your PC, make sure to save all necessary work to prevent data loss.

  • Using the Mouse
  • Select the Start menu.
Windows 10 Start button

  • By default it is in the lower left corner of your screen.
  • Select Power, then select Restart.
Start menu with Power and Restart highlighted.
  • Using the Keyboard
  • Press the Windows and X keys at the same time. This minimizes any open windows you may have.
Keyboard with Windows and X keys highlighted.
  • Press the Alt and F4 keys at the same time. This tells Windows to close the desktop.
Keyboard with Alt and F4 keys highlighted.
  • Select Restart, then OK.
Shut Down dialog with Restart and OK highlighted.

13. Reset Windows

Performing a Windows 10 Reset keeps your personal files, settings, and apps that came installed on your machine in-tact.

For portable devices: Before proceeding with a Reset, make sure the device is connected to a power outlet to avoid power loss during the reset process.

  1. Open the Start Menu, and select the Settings icon.
Windows 10 access settings from start menu.
  1. Scroll down and select Update & Security.
Windows 10 settings menu.
  1. Select Recovery.
Windows 10 update and security options within left-hand column.
  1. Click Get started under Reset this PC.
Windows 10 reset this PC prompt.
  1. Select Keep my files.
Windows 10 reset interface options.
  1. Take note of any apps that will need to be reinstalled. Click 'Next'.
Windows 10 reset interface affected programs list.
  1. If prompted with a Warning, click 'Next'.
Windows 10 reset interface warning prompt.
  1. At this point, the system is ready to be reset. This process may take quite a while, and the system will automatically restart when needed. Click Reset when ready.
Windows 10 reset ready to begin screen.
  1. Windows 10 will start the reset process and may reboot several times while running. Follow any on-screen instructions that may require your attention.
Windows 10 reset PC in process.
  1. Once the process is complete, you may use your system again.

14. What's next?