15 practical ways to fix a slow computer and improve performance

A computer that takes several minutes to start, freezes when opening applications, or struggles with ordinary tasks usually has a measurable performance problem.

The cause may be excessive background activity, limited memory, a nearly full drive, outdated software, malware, overheating, or failing hardware.

The most effective repair begins by identifying which resource is under pressure, then applying the appropriate fix.

The steps below focus primarily on Windows 11, with relevant guidance for Windows 10 and macOS.

Start with the diagnostic checks before changing settings or buying components.

Several improvements cost nothing, and they can reveal whether an upgrade is necessary.

Find the bottleneck

1. Check resource usage

Task Manager provides the quickest way to identify which component is limiting a Windows computer.

Press Ctrl + Shift + Esc, select the Processes tab, and review CPU, Memory, Disk, and GPU usage while the computer is slow.

Sort each column to see which applications consume the most resources.

A process that remains near the top while the computer freezes or responds slowly deserves investigation.

The Performance tab provides a broader view of CPU, memory, storage, and network activity.

High CPU usage can indicate a demanding application or a background process that has stopped responding.

Memory pressure often appears when several applications compete for limited RAM, while sustained disk activity can indicate heavy file operations or a storage problem.

Record what happens during the slowdown before closing processes, because the pattern can help identify the real cause.

2. Restart the computer

A restart closes running applications, clears temporary system states, and allows Windows to reload its services and drivers.

It can resolve slowdowns caused by applications that remain active after use, processes that stop responding, or updates that need a restart to finish.

Save open documents first, then select Start, Power, and Restart.

Test performance again after signing in, before opening all your usual applications.

Restarting is also a useful diagnostic step because it helps distinguish a temporary slowdown from a persistent problem.

If the computer runs normally for a short period and then becomes slow again, monitor Task Manager to identify what starts consuming resources.

A recurring slowdown after login may point to a startup application, cloud synchronization, antivirus activity, or a scheduled maintenance task.

Repeated restarts are not a permanent repair, but the change in performance can reveal when the problem returns.

Reduce background activity

3. Disable unnecessary startup apps

Applications configured to launch automatically can increase startup time and consume memory before you begin working.

Open Task Manager with Ctrl + Shift + Esc and select Startup apps.

Review the applications listed there, paying attention to their startup impact and whether you actually need them immediately after signing in.

Disable nonessential items such as launchers, update assistants, and applications that you can open manually.

Do not disable security software, hardware utilities, or services whose purpose you do not understand.

Audio drivers, touchpad software, backup tools, and business security agents may support functions that you rely on.

If the computer belongs to an organization, check with the IT administrator before changing managed startup settings.

Microsoft identifies startup applications as one of the common causes of slow Windows performance.

4. Close resource heavy apps

Some applications consume substantial CPU or memory even when they appear idle.

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Browsers with many open tabs, video editing software, large spreadsheets, virtual machines, and communication platforms can compete for the same resources.

In Task Manager, sort the Processes list by CPU or Memory and identify applications with unusually high usage.

Save your work before closing an application, particularly if it contains unsaved files or active downloads.

A high reading does not automatically mean that an application is faulty.

Video calls, file compression, software updates, and large exports can legitimately use significant resources for a limited period.

The useful distinction is whether the activity matches what you are doing.

If an application continues consuming resources after its task has finished, update it, restart it, or investigate whether an extension or background process is responsible.

5. Limit browser tabs

Modern websites can use considerable memory, especially when they contain video, interactive applications, advertising scripts, or live collaboration tools.

Keeping dozens of tabs open can leave less RAM available for desktop applications.

Close pages you no longer need and remove browser extensions that serve no regular purpose.

If a particular website causes the browser to become slow, test it in a private window or another browser to isolate the problem.

Google Chrome includes a Memory Saver setting that deactivates inactive tabs and reloads them when you return.

Open Chrome Settings, select Performance, and enable Memory Saver.

Its Moderate, Balanced, and Maximum options control how aggressively inactive tabs are deactivated.

This can help computers with limited memory, although pages that play audio, run downloads, or support active calls may remain active.

6. Restrict background apps

Some applications continue running background tasks after you close their main windows.

These tasks may synchronize files, check for updates, deliver notifications, or maintain connections to online services.

In Windows 11, open Settings, select Apps, then Installed apps.

Open the menu for a supported application, choose Advanced options, and change its background app permission when that control is available.

Apply this selectively.

Cloud backup, email synchronization, security monitoring, and communication tools may need background access to perform their intended functions.

Disabling every background permission can interfere with services you expect to work automatically.

Focus on applications that provide little value when inactive, and check whether resource usage falls after the change.

Recover storage capacity

7. Free up disk space

A system drive with very little free space can interfere with updates, temporary files, application operations, and other system tasks.

Open Settings, select System, then Storage to review how much space Windows uses.

Check Temporary files and remove items that you no longer need.

Review large downloads, old installers, duplicate archives, and unused files before deleting anything permanently.

Windows Storage Sense can automate parts of this process by removing temporary files and managing selected storage categories.

Open Settings, System, Storage, and Storage Sense to review its options.

Check the settings carefully because automatic cleanup may affect items in the Recycle Bin or Downloads folder, depending on your configuration.

Microsoft recommends storage cleanup as one of its standard performance troubleshooting measures.

8. Remove unused programs

Installed applications occupy storage and may add background services, scheduled tasks, browser components, or startup entries.

Open Settings, select Apps, then Installed apps.

Sort the list by size to identify large programs you no longer use.

Uninstall software through Windows settings or the application's own uninstaller rather than deleting its folders manually.

Take care with drivers, Microsoft components, hardware utilities, and applications supplied by your computer manufacturer.

Their names may not make their purpose obvious, and removing them can affect device functions.

If you do not recognize a program, search for its publisher and purpose before uninstalling it.

Removing unused software is most useful when it also eliminates unnecessary background activity or recovers meaningful storage capacity.

9. Check drive health

A storage device that is beginning to fail can cause freezing, slow startup, delayed file access, and unexpected errors.

Treat these symptoms seriously if they appear alongside unusual noises from a mechanical hard drive or repeated file corruption.

Windows 11 can display certain critical warnings for supported NVMe drives under Settings, System, Storage, Advanced storage settings, and Disks & volumes.

Open the affected drive's Properties to inspect the available health information.

Microsoft identifies warnings such as degraded reliability, low spare capacity, and read only status.

Its health monitoring does not cover every storage type: the documented Windows feature monitors NVMe SSDs, not SATA SSDs or traditional hard drives.

A missing warning therefore does not prove that a drive is healthy.

If you suspect a failing disk, back up important files immediately and use the manufacturer's diagnostic utility or a qualified technician to assess it.

Correct software problems

10. Install system updates

Operating system updates can include bug fixes, security improvements, driver updates, and compatibility changes.

Open Settings, select Windows Update, and choose Check for updates.

Install available updates from trusted sources, then restart if Windows requests it.

If a slowdown began immediately after a specific update, record the update date and check the manufacturer's support information before attempting to remove it.

Optional driver updates appear under Windows Update, Advanced options, and Optional updates.

Install only drivers that apply to your hardware or resolve a known issue.

For graphics, chipset, network, or storage problems, the computer manufacturer's support page may provide a more suitable package.

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Avoid third party driver updater applications that promise to update every component automatically, since they can introduce incompatible or unnecessary software.

11. Scan for malware

Malware can consume CPU, memory, disk, and network resources while also exposing personal or business information.

Unexplained browser redirects, persistent advertisements, unfamiliar processes, disabled security settings, and unexpected network activity may justify a security investigation.

Open Windows Security, select Virus & threat protection, and run a Quick scan.

If the symptoms persist or there are stronger signs of infection, use the available scan options for a more thorough examination.

Use one reputable, actively maintained antivirus product rather than installing several real time security suites.

Multiple antivirus applications can compete for resources and interfere with one another.

Dell specifically warns that installing more than one antivirus or antimalware program does not provide better protection and may slow a computer further.

Keep security definitions current and avoid downloading cleanup tools from unfamiliar websites.

12. Test with a clean boot

A clean boot starts Windows with essential drivers and a reduced set of startup services.

It helps determine whether a third party application or service is interfering with normal operation.

Search for System Configuration, open the Services tab, select Hide all Microsoft services, and then choose Disable all.

Open the Startup tab, launch Task Manager, and disable the enabled startup applications before restarting.

Use this procedure carefully, especially on a work computer.

Microsoft warns that network policies may restrict these changes and that altering advanced startup settings without guidance can make a device unusable.

If performance improves after a clean boot, re enable services and startup applications in controlled groups until the slowdown returns.

Restore normal startup settings after testing, and remove or update the application responsible for the conflict.

13. Adjust visual effects

Windows animations, transparency, shadows, and other visual effects use system resources.

Their impact is usually modest on a modern computer, but reducing them can improve responsiveness on older machines with limited graphics capability.

Search Windows for Adjust the appearance and performance of Windows, open the Performance Options window, and select Adjust for best performance.

You can also disable individual effects if you prefer to retain smoother window movement or readable interface details.

The setting changes appearance rather than fixing a hardware or software fault.

If the computer remains slow while opening files, switching applications, or starting Windows, investigate memory, storage, and background activity as well.

Visual adjustments are most useful when the interface itself feels sluggish and the hardware has limited capacity.

They should be treated as a low risk optimization rather than a substitute for diagnosis.

Address hardware limits

14. Check power and cooling

A laptop can run more slowly when its power settings prioritize battery life or when its cooling system cannot remove heat effectively.

In Windows 11, open Settings, System, then Power & battery.

Under Power mode, select Best performance when the computer is connected to power and the workload needs maximum responsiveness.

This setting can increase energy use, fan noise, and operating temperature, so it is not ideal for every situation.

Heat can cause a processor to reduce its operating speed to protect itself.

Intel describes this behavior as thermal throttling, a mechanism that lowers CPU clock speed when temperatures reach the processor's protection threshold.

Check that air vents remain unobstructed, use a laptop on a hard surface, and make sure fans operate normally.

If the computer becomes unusually hot or its fans run loudly during light tasks, arrange a proper inspection and cleaning rather than opening the device without the required experience.

15. Upgrade RAM or storage

Hardware upgrades can deliver a more meaningful improvement when software changes have not resolved the slowdown.

Additional RAM can help when the computer becomes unresponsive while several applications or browser tabs are open.

An SSD can make a particularly noticeable difference on a computer that still uses a mechanical hard drive, improving startup and file access.

Kingston's guidance emphasizes that the right upgrade depends on whether memory capacity or storage performance is the actual limitation.

Check the computer's model specifications before buying components.

Memory may be soldered to the motherboard, limited by the processor, or restricted by the number of available slots.

Storage upgrades also require the correct physical size and interface, such as SATA or NVMe.

Back up your files before replacing a drive, and confirm that the new component is compatible with the computer and operating system.

If the processor or graphics hardware is too old for the applications you need, an upgrade may offer limited value compared with replacing the computer.

A useful upgrade decision starts with the evidence from Task Manager.

If memory remains nearly full during normal work, check the maximum supported RAM and the cost of a compatible module.

If disk activity remains high and the computer has a hard drive, an SSD may be the better first investment.

Avoid buying memory simply because a computer feels slow: adding RAM will not fix a failing drive, malware infection, thermal throttling, or a processor that cannot meet the workload.

When basic fixes fail

A persistent slowdown after these checks may indicate damaged system files, a failing component, or an operating system problem that requires specialist diagnosis.

Check the manufacturer's hardware diagnostics and Windows reliability information for recurring errors.

Dell, for example, provides preboot diagnostics for supported computers, which can help identify hardware faults before Windows loads.

Record any diagnostic error code and retain a backup before attempting repairs that could affect personal files.

Mac users can apply the same diagnostic principle with macOS tools.

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Open Activity Monitor to identify applications consuming unusually high CPU or memory, and review Storage under System Settings, General.

Apple also recommends checking available startup disk space, quitting incompatible or unused applications, and using Disk Utility to verify a disk when storage problems are suspected.

The menu names can vary by macOS release, so follow the instructions for the installed version.

Avoid registry cleaners, aggressive optimization suites, and utilities that promise dramatic speed increases through one click.

They can remove settings or files that Windows and installed applications need, while adding another background process to the system.

Windows already includes tools for storage cleanup, startup management, security scanning, and performance monitoring.

Use those tools first, make one change at a time, and compare the computer's behavior after each change.

A useful test is to compare performance under the same conditions.

Restart the computer, wait for startup activity to settle, and open the same applications that usually cause trouble.

Note whether the delay occurs during startup, when opening files, while browsing, or during demanding work.

These distinctions matter because a computer that starts slowly may have a storage or startup problem, while one that slows down during multitasking may need more memory.

Pay attention to when the problem first appeared.

A sudden change after installing an application, connecting a peripheral, updating a driver, or changing security software can provide a valuable lead.

Windows System Restore may help reverse certain system changes when a suitable restore point exists, although it does not replace a backup of personal files.

If hardware diagnostics report an error, prioritize data protection and repair over further software optimization.