How to Speed Up a Slow Computer

A slow Windows computer rarely has one obvious cause. It might take minutes to reach a usable desktop, freeze when you switch between apps or load websites badly while everything else feels fine, and each of those needs a different fix.

Guessing is where the time and money go. People buy RAM when the hard drive is the problem, or reinstall Windows over a fault that one startup app was causing. If you want to know how to speed up a slow computer properly, the answer starts with finding the bottleneck during the exact task that feels slow, then changing one thing and checking that task again.

Task Manager, the process and resource monitor built into Windows, is enough for the first round of checks, and Microsoft’s own performance tips cover the same built-in route. This guide is for Windows PCs. If you’re on a Mac, my Mac performance guide is the better starting point.

Find the Cause First

Save your work and restart before anything else, because a restart clears stuck updates and processes that have been running for days. Then open the app or file that usually feels slow and watch what the computer is doing during the delay. A reading taken while the PC sits idle may not explain a pause that only happens under load.

Two questions narrow it down quickly. Did it become slow suddenly, after an update, driver or new app, or gradually over months? And is the whole computer slow, or only websites? A sudden change points at the recent change. A web-only problem points at the browser or the connection rather than the hardware.

Say Windows is installing updates and Task Manager shows the disk at 100%. That doesn’t mean the drive needs replacing. You should see whether the activity settles once the update finishes, and whether the same delay remains during your ordinary work.

Check CPU, Memory and Disk Activity

Press Ctrl + Shift + Esc to open Task Manager. The Processes tab shows which app is using the CPU, memory and disk, and the Performance tab shows how busy each part is over time. These readings need context. High CPU use while you export a video is expected, and high CPU use after you’ve closed everything is not.

During the slowdown, you should check:

• The process using the resource, and whether its work is expected.
• Whether the activity is a brief spike or continues through the task.
• Whether memory and disk activity rise together.
• Whether closing an optional app improves the same task.

Disk at 100% describes how busy the drive is, not how full it is. Windows Update, a security scan and paging (Windows moving memory to the drive when RAM runs short) can all push it there. You should check free space separately and find the process behind the activity before choosing an SSD or more RAM. There’s no point buying a cooling pad or a RAM kit when the real problem is a slow mechanical hard drive.

A memory reading of 85% isn’t an automatic reason to buy RAM either. Windows uses spare memory for caching, so a high number on its own is normal. What matters is whether switching between your usual apps causes repeated pauses while available memory stays low. If it does, reduce the workload and compare again. If the pauses continue, more RAM may help, provided the machine can take it.

For a deeper look, Microsoft’s free Process Explorer shows more detail about each process than Task Manager does. Most people won’t need it.

Check Startup Apps

Startup cleanup is the best free fix when sign-in takes too long or optional apps keep working in the background. You can stop an app from launching at startup without uninstalling it.

1. Open Task Manager and go to Startup apps.
2. Find an optional app you recognize, such as a game launcher, chat app or update helper.
3. Disable its automatic startup.
4. Restart, then compare how long it takes to reach a usable desktop.

Security software, backup tools, work VPN clients and the utilities for your touchpad, audio or graphics may need to start automatically. A “High” startup impact label is a reason to look closer, not proof that the entry is safe to disable.

Autoruns, another free Microsoft tool, shows a much wider list that includes services, scheduled tasks and drivers. Its option to hide Microsoft entries makes the list easier to read, but a third-party entry left on screen can still be essential, so you should research an entry before disabling it.

Free Disk Space Safely

Windows and your apps need free space for updates and temporary work. How much depends on the drive and what you do with it, so I would go by Windows’ own low-space warnings and what is actually taking up the space rather than one fixed percentage.

1. Open Settings > System > Storage.
2. Open Temporary files and read each category before selecting it.
3. Check the Downloads and Recycle Bin selections against files you still need.
4. Review Storage Sense’s cleanup schedule and its cloud-file settings.
5. Copy large personal files you want to keep to another drive, check the copy, then delete the original.

Storage Sense can also make OneDrive files online-only. That frees local space without deleting the cloud copy, but you’ll need a connection to open those files again, so files you need offline should stay on the PC.

WizTree shows where the space went, which helps when a few huge folders such as old ISO files, videos or game installs are the problem. It is free for personal use and needs a paid license for business use. BleachBit can clear caches, but you should preview what it will delete and leave browser data alone unless you mean to remove it. Clearing every cache on a schedule just makes apps rebuild them, so it shouldn’t become a weekly speed ritual.

Remove Unused Apps

An unused app matters most when it takes space you need or keeps background updaters and services running. You should start with Settings > Apps > Installed apps and remove software you recognize and no longer use.

BCUninstaller is a free tool for removing many apps at once and finding the leftovers they leave behind. Review its choices before accepting a batch, and leave drivers, Visual C++ runtimes, .NET and work software alone unless you know why they are there.

A restore point helps roll back system changes, but it doesn’t bring back personal files deleted by a cleanup. Back up important files separately before any big removal.

Check Browser Performance

If your local apps are responsive and only websites feel slow, the browser or the connection is the place to look. A RAM or SSD purchase won’t fix a slow connection or a heavy extension.

You should close unused tabs, remove extensions you don’t recognize and compare another website or device on the same connection. Coupon, toolbar, downloader and “search assistant” extensions are common culprits. If the homepage or search engine keeps changing on its own, reset the browser’s settings.

Chrome’s Memory Saver and Edge’s sleeping tabs free memory from tabs you aren’t using, and those tabs reload when you return to them. Switching browsers is worth a test if your normal sites still run poorly, but no browser is lighter for every set of sites and extensions. For lag in online games, my internet speed for gaming guide covers a different problem from a slow PC.

Check Heat and Power

A laptop can slow itself down because of a power limit or a heat limit. A hot keyboard or a loud fan is a reason to investigate, but on its own it doesn’t prove the processor is throttling.

You should repeat the same task with the original charger connected and the Windows power mode set to Best performance. That mode increases heat and battery use, so it is a setting for heavy work rather than one every laptop should keep. If performance drops during sustained work, check temperature and clock speed together. LibreHardwareMonitor shows both, and a falling clock speed at high temperature is the sign of thermal throttling.

Keep the vents clear and use the laptop on a firm, flat surface, since beds and blankets block the intake. If you blow dust out of the vents, hold the fan still, because letting a small laptop fan spin freely can damage it. Internal cleaning and thermal paste work should follow your model’s service guide, or go to a repair shop if you aren’t comfortable opening the machine.

Check Malware and Windows Health

Malware and adware can make a decent PC feel broken. You should update Microsoft Defender and run a scan, and run Malwarebytes Free as a second opinion if the machine still behaves strangely. A clean quick scan is a good sign, though not proof that nothing is wrong. If you see popups, redirects or fake warnings, my guide to the unexpected signs your computer has a virus comes before any performance work.

Drivers should come from Windows Update or your PC maker’s support site. Driver-updater utilities often pull drivers from unofficial sources and can create new problems. If the slowdown started right after an update, look at that update or driver first instead of reinstalling Windows.

If Windows features fail or system files may be damaged, Microsoft’s repair sequence is DISM first and SFC second. Run these in Command Prompt as administrator and let each finish:

DISM /Online /Cleanup-Image /RestoreHealth
sfc /scannow

These commands repair Windows files. They don’t speed up a healthy system, and they can’t fix a failing drive.

Choose an SSD or RAM Upgrade

Upgrades come after the checks above, because a part only helps when it removes the bottleneck you found. Prices matter more than they used to. SSD and memory prices have climbed steeply in 2026 because AI servers are absorbing so much flash and DRAM supply, so you should price the exact part before deciding an upgrade is the cheap fix.

SSD

An SSD is worth it when an otherwise usable PC still runs Windows from a mechanical hard drive and Task Manager shows that drive holding up boot, app launches and updates. Before buying, check your model’s manual for both the physical size and the interface. M.2 is a shape, and an M.2 drive can be SATA or NVMe, so the manual decides what fits. A 2.5-inch SATA drive such as the Samsung 870 EVO suits laptops and desktops that took a 2.5-inch hard drive.

Micron stopped shipping Crucial consumer products after February 2026, though it still honors warranties. Leftover Crucial MX500 stock is fine to buy if the price is right, but you should check the seller before treating it as a current product.

Before you swap the drive, you should have:

• A separate backup of the files you need.
• A compatible drive with room for your current data and some growth.
• The right adapter or enclosure, and a plan to either clone the old drive or install Windows fresh.
• Your BitLocker recovery key and app license details.
• A check that Windows boots and your files and apps work before you erase the old drive.

Check Windows Support

An upgrade should fit how long the computer can stay supported. Microsoft’s ordinary support for Windows 10 ended on October 14, 2025. Its consumer Extended Security Updates program now gives enrolled PCs security updates through October 12, 2027.

• Enrollment is free if you sync your PC settings, or costs 1,000 Microsoft Rewards points or a one-time $30.
• The PC needs Windows 10 version 22H2 with the latest updates and an administrator Microsoft account.
• Work PCs joined to a domain or managed by an MDM tool aren’t eligible and use a separate business program.
• ESU covers security updates only, with no new features or full technical support.

You should check Windows 11 compatibility before buying parts for an old Windows 10 machine. A new SSD or more RAM doesn’t make unsupported hardware eligible. If replacement is the sensible choice, my laptop buying checklist helps you pick a machine for the work you do.

Optional PowerShell Checks

These are for readers comfortable with PowerShell on Windows. They only show information, so a normal PowerShell window is enough.

Get-Process |
  Sort-Object WorkingSet64 -Descending |
  Select-Object -First 15 Name, Id,
    @{Name='WorkingSet_MiB';Expression={[math]::Round($_.WorkingSet64 / 1MB, 1)}}

Get-CimInstance Win32_StartupCommand |
  Select-Object Name, Command, Location, User |
  Sort-Object Name

winget upgrade

winget show --id Microsoft.Sysinternals.Autoruns --exact --source winget
winget install --id Microsoft.Sysinternals.Autoruns --exact --source winget

powercfg /batteryreport /output "$env:USERPROFILE\battery-report.html"

Slow Only in Games

If the PC is fine everywhere except games, the graphics hardware is usually the limit. Lowering the resolution, turning on FSR or XeSS upscaling where the game offers it and capping the frame rate at a level your hardware can hold steadily do more than registry tweaks. You should also update the GPU driver from Intel, NVIDIA or AMD and close launchers and browsers while you play.

Lag spikes in online games with otherwise smooth frame rates point at the network rather than the PC.

What I’d Skip

Some old speed-up advice does nothing on a modern PC or creates new problems. I would skip these unless you have a very specific reason:

• Registry cleaners, which rarely make a noticeable difference and can break apps.
• ReadyBoost, which only ever helped hard-drive systems and does nothing on an SSD.
• Disabling Windows Update permanently, which leaves the machine exposed instead of fixing the update problem.
• Stacking several optimizer apps, whose overlapping background services can make the PC slower.
• Running debloat scripts from the internet because a video promised more FPS. Some remove Store components or recovery features you’ll need later.

When to Repair or Replace

Some problems need a repair shop or a decision, not another tweak. Disk errors, repeated crashes, a fan that doesn’t spin or hardware too old for a supported Windows version all fall here.

Resetting Windows can help when the software is badly damaged, but it doesn’t repair hardware or make an old PC eligible for Windows 11. You should back up first, keep your license keys and expect to reinstall apps even when personal files are kept. If the repair costs more than the machine is worth to you, replacing it is the sensible choice.

FAQs on Slow Computers

Check the Result

After each change, repeat the same task under the same conditions: same apps open, same power source. If it now runs well, you can stop there. There is no benefit in completing every tweak on a list.

If the delay remains, go back to what the computer was doing during that delay. A failing drive, a bad driver or a power limit each need a different response from an optional startup app, and that evidence should decide your next step before you buy another part or install another utility.

Disclaimer: This site is reader-supported. If you buy through some links, I may earn a small commission at no extra cost to you. I only recommend tools I trust and would use myself. Your support helps keep gauravtiwari.org free and focused on real-world advice. Thanks. - Gaurav Tiwari