PC & LAPTOP TROUBLESHOOTING GUIDE

Why Is My Computer So Slow? 15 Proven Fixes to Speed Up a Slow PC or Laptop (Windows 10 & 11 Guide)

By the Fixspert Team  |  Reading time: about 15 minutes  |  Works on Windows 10 and Windows 11

A computer that takes five minutes to start, freezes when you open a browser, or fans that scream while you type an email is one of the most frustrating problems in everyday computing. The good news: in most cases a slow PC or laptop is not dead, and you do not need to buy a new one. The cause is usually too many startup programs, a nearly full drive, outdated software, malware, or a drive and memory setup that cannot keep up.

This guide walks you through 15 fixes in the order that gets results fastest, from free 2-minute tricks to hardware upgrades. Each step shows you exactly where to click. We also include a cybersecurity check, because hidden malware and crypto-miners are a very common cause of sudden slowness.

Quick answer: The five fixes that solve most slow-PC problems are: (1) restart and install updates, (2) disable startup programs, (3) free up disk space, (4) scan for malware, and (5) upgrade from a hard disk (HDD) to an SSD. If you only have ten minutes, do those five.

In This Guide

• Common causes of a slow PC or laptop

• 15 step-by-step fixes with screenshots (Steps 1-15)

• Bonus: fix a slow web browser

• Cybersecurity check: is malware slowing your PC?

• Monthly maintenance checklist, FAQ, and where to get free help online

Why Is My PC or Laptop Running Slow? The Most Common Causes

Before fixing anything, it helps to know what you are dealing with. Slow performance almost always comes from one of the causes below.

Before You Begin: Back Up Your Files

Most steps below are safe, but it is smart to protect your data first. Copy your important documents, photos, and work files to an external drive or a cloud service such as OneDrive or Google Drive. If you need help recovering files or choosing a backup method, our team at Fixspert can guide you online.

Warning: Never download "PC speed booster" or "driver updater" programs from random websites or pop-up ads. Many are scams or malware themselves. Everything in this guide uses tools already built into Windows or well-known official software.

Step-by-Step: How to Fix a Slow PC or Laptop

Step 1: Restart Your Computer and Install Windows Updates

A restart clears memory and stops stuck background processes. Many people keep their laptop in sleep mode for weeks, which slowly drags performance down. Pending updates can also slow the system while they download in the background.

1. Save your work, then click Start > Power > Restart. (Do not choose "Shut down" if Fast Startup is on, because it may not fully clear memory.)

2. After restart, open Settings (press Windows key + I).

3. Click Windows Update and then Check for updates.

4. Install everything offered, including optional driver updates under Advanced options > Optional updates, then restart again.

Figure 1: Windows Update page in Settings with the Check for updates button (illustration)

Step 2: Use Task Manager to Find What Is Slowing You Down

Task Manager shows exactly which program is eating your CPU, memory, disk, or network. This is the single best diagnostic tool in Windows.

1. Press Ctrl + Shift + Esc to open Task Manager. If it opens in a small window, click More details.

2. On the Processes tab, click the CPU, Memory, and Disk column headings to sort from highest to lowest.

3. Look for anything using more than about 50% CPU or a large amount of memory when you are not actively using it.

4. If it is a program you do not need, right-click it and choose End task. Do not end items you do not recognize without searching their name first, and never end "System" or "Windows" processes.

Figure 2: Task Manager Processes tab sorted by CPU usage (illustration)

Pro tip: If the Disk column sits at 90-100% for long periods, you probably have an old hard disk (HDD) or a failing drive. Jump to Step 6. If an unknown program uses high CPU while you are idle, go to Step 9 and the Cybersecurity section.

Step 3: Disable Unnecessary Startup Programs

Every program set to launch at startup lengthens boot time and uses memory all day. This is often the biggest free speed improvement.

1. Open Settings > Apps > Startup (Windows 11) or press Ctrl + Shift + Esc and click the Startup apps tab.

2. Check the Startup impact column. Anything marked High deserves a second look.

3. Switch off programs you do not need immediately at login: music players, game launchers, chat apps, printer utilities, "updaters", and cloud tools you rarely use.

4. Keep your antivirus / Windows Security, touchpad drivers, and audio drivers enabled.

5. Restart and notice the difference in boot time.

Figure 3: Startup apps list with high-impact programs turned off (illustration)

Step 4: Free Up Disk Space

Windows needs free room to work. When your system drive (usually C:) is more than 85-90% full, performance drops and updates may fail. Aim to keep at least 15-20% free.

Check how full your drive is

1. Open Settings > System > Storage.

2. Look at the bar for your C: drive and click Temporary files or Show more categories to see what is using space.

Clear temporary files safely

1. Under Temporary files, tick Temporary files, Thumbnails, Delivery Optimization Files, and Recycle Bin (check it first so you do not delete anything you need).

2. Click Remove files.

3. Turn on Storage Sense (Settings > System > Storage > Storage Sense) so Windows cleans up automatically.

Figure 4: Windows Storage settings showing temporary files to remove (illustration)

For very large files, move videos, old downloads, and photo archives to an external drive or cloud storage. A free tool such as TreeSize Free or WinDirStat (download only from the official sites) shows you the biggest folders at a glance.

Step 5: Uninstall Programs You No Longer Use

1. Go to Settings > Apps > Installed apps (Windows 11) or Apps > Apps & features (Windows 10).

2. Click the Sort option and choose Size or Install date.

3. Click the three dots (or the app name) next to anything you no longer need, then choose Uninstall.

4. Pay special attention to trial software, old toolbars, "PC cleaner" or "optimizer" apps, and programs you do not remember installing. These are common slowdown and adware sources.

Figure 5: Installed apps list sorted by size with Uninstall option (illustration)

Step 6: Check Your Drive Type and Health (HDD vs SSD)

If your computer uses a traditional hard disk drive (HDD), it will feel slow compared with a modern solid-state drive (SSD), no matter how much you clean it. A drive that is failing will also cause freezes and sudden slowdowns.

Find out whether you have an HDD or SSD

1. Right-click Start and choose Terminal (Admin) or Windows PowerShell (Admin).

2. Type the command below and press Enter:

Get-PhysicalDisk | Select-Object FriendlyName, MediaType, HealthStatus

3. Under MediaType, you will see HDD or SSD. HealthStatus should say Healthy.

Figure 6: PowerShell output showing disk media type and health status (illustration)

Check detailed drive health (free)

Download CrystalDiskInfo from its official website and open it. A status of Good is fine. Caution or Bad means you should back up your data immediately and replace the drive.

Figure 7: CrystalDiskInfo showing drive health status (illustration)

Important: If your system drive is an HDD, upgrading to an SSD is the single biggest speed boost you can make. It often makes a 5-year-old laptop feel almost new. See Step 14.

Step 7: Check Your RAM Usage

RAM (memory) is your computer's short-term workspace. When it runs out, Windows uses the much slower drive instead, and everything lags.

1. Open Task Manager (Ctrl + Shift + Esc) and click the Performance tab.

2. Select Memory. Check the percentage in use while you are doing your normal work.

3. If memory use is regularly above 80-85%, you need to close heavy apps (especially many browser tabs) or add more RAM.

Figure 8: Task Manager Performance tab showing memory usage (illustration)

Step 8: Change Your Power Mode (Especially on Laptops)

Windows can throttle your processor to save battery. This is the reason many laptops feel slow when unplugged.

1. Open Settings > System > Power & battery (Windows 11) or Settings > System > Power & sleep (Windows 10).

2. Set Power mode to Best performance (Windows 11), or open Additional power settings and choose High performance or Balanced (Windows 10).

3. Make sure Battery saver is not turned on while you are working.

Figure 9: Windows power mode set to Best performance (illustration)

Note: Best performance uses more battery and generates more heat, so use it when plugged in or when you really need speed.

Step 9: Scan for Viruses and Malware

Malware, adware, and hidden crypto-mining programs quietly use your CPU and memory. If your PC became slow suddenly, this step is essential. (See the full Cybersecurity Check section later in this guide.)

1. Open Start, type Windows Security, and press Enter.

2. Click Virus & threat protection.

3. Click Scan options, choose Full scan, and click Scan now. This may take an hour or more; you can keep working.

4. For stubborn infections, choose Microsoft Defender Antivirus (offline scan). Your PC will restart and scan before Windows loads.

5. Follow the prompts to remove or quarantine anything found, then restart.

Figure 10: Windows Security scan options showing Full scan (illustration)

As a second opinion, you can run a one-time scan with Malwarebytes Free (official site only). Do not run two real-time antivirus programs at the same time, as they can conflict and slow your PC.

Step 10: Update Your Drivers

Outdated graphics, chipset, Wi-Fi, and storage drivers can cause lag, stuttering, and crashes.

1. Right-click Start and choose Device Manager.

2. Expand Display adapters, right-click your graphics card, and choose Update driver > Search automatically for drivers.

3. For best results, visit the support page of your laptop or motherboard maker (Dell, HP, Lenovo, ASUS, Acer, MSI) or the chip maker (Intel, AMD, NVIDIA) and download the latest driver for your exact model.

4. Restart after installing.

Figure 11: Device Manager showing the Update driver option (illustration)

Step 11: Reduce Visual Effects

Animations and transparency look nice but use graphics and CPU power. On older or low-spec machines, turning them down makes Windows feel snappier.

1. Press Windows key + R, type sysdm.cpl, and press Enter.

2. Open the Advanced tab and click Settings under Performance.

3. Choose Adjust for best performance, or choose Custom and keep only Smooth edges of screen fonts ticked.

4. Click Apply and OK.

5. Also turn off transparency: Settings > Personalization > Colors > Transparency effects: Off.

Figure 12: Performance Options window with Adjust for best performance selected (illustration)

Step 12: Repair Corrupted System Files (SFC and DISM)

Damaged Windows files can cause crashes, slow performance, and apps that will not open. Windows includes two repair tools.

1. Right-click Start and choose Terminal (Admin) or Windows PowerShell (Admin).

2. Run the System File Checker and wait until it reaches 100%:

sfc /scannow

3. Then run the deeper repair tool (needs internet, can take 10-20 minutes):

DISM /Online /Cleanup-Image /RestoreHealth

4. When both finish, restart your computer.

Figure 13: Command window showing sfc /scannow results (illustration)

Note: If SFC says it found and could not fix corrupt files, run DISM first and then run SFC again.

Step 13: Fix Overheating and Clean the Dust

When a processor gets too hot, it deliberately slows down to protect itself. This is called thermal throttling, and it is very common in laptops that are a few years old.

Signs of overheating

• Fans running loudly almost all the time

• The bottom of the laptop or the case feels very hot

• The PC slows down or shuts off suddenly during heavy tasks or games

What to do

• Use the laptop on a hard, flat surface, not on a bed, sofa, or blanket. A cooling pad helps.

• Use compressed air to blow dust from the vents and fans (power off and unplug first). For a deep clean or fresh thermal paste, ask a technician if you are not comfortable opening the device.

• Monitor temperatures with a free tool such as HWiNFO or HWMonitor. Sustained temperatures above about 90 C under load are a concern.

Figure 14: Hardware monitor showing CPU temperature (illustration)

Step 14: Upgrade Your Hardware (SSD and RAM)

If the software fixes above did not help enough, hardware is probably the limit. Two upgrades give the best value:

• Replace the HDD with an SSD. This improves boot time, app launches, and overall responsiveness more than any other single change. Many laptops can be upgraded at home or at a repair shop.

• Add more RAM. Going from 4 GB to 8 GB, or from 8 GB to 16 GB, makes multitasking noticeably smoother. Check your exact model's maximum supported RAM and memory type (DDR3, DDR4, or DDR5) before buying.

Tip: Not sure which SSD or RAM fits your laptop? Ask the experts at Fixspert for a quick compatibility check before you spend money.

Step 15: Last Resort - Reset or Reinstall Windows

If your PC is still slow after everything above, a clean Windows install removes years of accumulated clutter and hidden problems. Back up all your files first.

1. Open Settings > System > Recovery.

2. Under Reset this PC, click Reset PC.

3. Choose Keep my files (removes apps and settings but keeps personal files) or Remove everything (a complete fresh start).

4. Choose Cloud download for a fresh copy of Windows, then follow the prompts.

Figure 15: Reset this PC option in Windows Recovery settings (illustration)

Bonus: Fix a Slow Web Browser

Sometimes the computer is fine and only the browser is slow. Try these quick fixes:

• Close unused tabs. Each tab uses memory. Use the browser's built-in memory-saver or sleeping-tabs feature.

• Remove extensions you do not use. Open your browser's extensions page and remove anything unfamiliar. Malicious extensions are a major cause of slowness and pop-ups.

• Clear cache and cookies from the browser's settings under Privacy.

• Update the browser to the latest version.

Figure 16: Browser extensions page used to remove unwanted extensions (illustration)

Cybersecurity Check: Is Malware Making Your PC Slow?

A slow computer is not always an old computer. Malware, spyware, adware, and cryptojacking programs are a very common hidden cause of slowness, and they also put your passwords, banking details, and personal files at risk. Use this section as a security health check.

Warning Signs Your PC May Be Infected

• The computer became slow suddenly, even though nothing changed

• High CPU or disk usage in Task Manager when you are not doing anything

• Pop-ups, new toolbars, or your browser home page and search engine changed on their own

• Programs you did not install, or security software that is turned off by itself

• Fans running at full speed while the PC is idle (a sign of crypto-mining)

• Friends receiving strange emails or messages from your accounts

• Files renamed, locked, or a message demanding payment (ransomware: disconnect from the internet immediately)

Cybersecurity Checklist: What to Do Now

1. Disconnect from the internet if you suspect an active infection (turn off Wi-Fi or unplug the network cable).

2. Run a full scan and an offline scan with Windows Security (see Step 9).

3. Check installed programs and browser extensions and remove anything unfamiliar.

4. Check startup items (Step 3) for suspicious entries.

5. Change your passwords from a different, clean device, starting with email, banking, and social media. Turn on two-factor authentication (2FA) everywhere possible.

6. Check your accounts for unknown logins or forwarding rules, especially your main email account.

7. Update everything: Windows, your browser, Office, and other apps. Updates close known security holes.

8. If problems continue, back up your important files and reset Windows (Step 15). Scan your backups before restoring them.

Figure 17: Windows Security overview page with protection status (illustration)

How to Stay Protected Going Forward

• Keep Windows Security (Microsoft Defender) turned on and let Windows Update run automatically.

• Never install cracked or pirated software. It is one of the top ways malware reaches home PCs.

• Download only from official websites or trusted stores. Decline bundled "extras" during installation.

• Be careful with email attachments and links. If a message creates urgency ("Your account will be closed!"), stop and verify it separately.

• Use a password manager and unique passwords for every account.

• Follow the 3-2-1 backup rule: 3 copies of your data, on 2 different storage types, with 1 copy off-site or in the cloud.

• Use a standard (non-administrator) account for daily work.

• Avoid public Wi-Fi for banking or use a trusted VPN.

Beware of fake support scams: A pop-up that says "Your PC is infected - call this number" is a scam. Real Microsoft or antivirus alerts never ask you to phone a number, pay with gift cards, or give someone remote access. Only allow remote access from someone you contacted yourself and trust.

Worried your PC has been compromised? Our team can help you check it safely at Fixspert Online Help.

How to Keep Your PC Fast: Monthly Maintenance Checklist

Still Slow? Get Free Help Online

Every computer is different, and sometimes the cause is hidden or the fix is risky to try alone. If you have followed this guide and your PC or laptop is still slow, or you would rather have an expert guide you, we are here.

• Get expert PC and laptop help online at Fixspert

• Ask a question and get step-by-step troubleshooting guidance

• Request a cybersecurity and malware check

• Browse more Windows, laptop, and software fix guides

When you contact us, it helps to have your computer's make and model, your Windows version, and a short description of when the slowness started.

Frequently Asked Questions

Why is my laptop so slow all of a sudden?

Sudden slowness usually points to a background update, a program using too much CPU or memory, a nearly full drive, or malware. Open Task Manager (Ctrl + Shift + Esc) to see what is using resources, then run a full Windows Security scan.

How can I speed up my PC for free?

Restart, install updates, disable startup programs, delete temporary files, uninstall unused apps, scan for malware, and set the power mode to Best performance. All of these are free and built into Windows.

Will adding more RAM make my computer faster?

It will if your memory regularly runs above about 80-85%. If your system drive is an old hard disk, upgrading to an SSD usually gives a bigger improvement than RAM.

Does a virus make a computer slow?

Yes. Malware, adware, and crypto-mining programs can use your processor, memory, and internet connection in the background. A slow PC with high CPU use while idle, pop-ups, or redirects should be scanned immediately.

Is it worth upgrading an old laptop instead of buying a new one?

Often yes. If the processor is still reasonably modern, adding an SSD and more RAM can extend a laptop's life by years at a fraction of the cost of a new machine.

Should I use PC cleaner or optimizer software?

Generally no. Most do little that Windows cannot already do, and some are scams or adware. Use the built-in tools in this guide instead.

How often should I restart my PC?

At least once a week, and whenever Windows asks you to after updates. Restarting clears memory and finishes pending updates.

Conclusion

A slow PC or laptop is rarely a lost cause. Start with the quick wins (restart, updates, startup programs, free disk space, and a malware scan), then move on to power settings, drivers, system repair, cooling, and finally hardware upgrades. Keep your system protected with updates, backups, and careful browsing so the slowness does not come back.

If you want a fast, safe fix without the guesswork, Fixspert is ready to help you get your computer running like new.

Disclaimer: Menu names can differ slightly between Windows versions and device makers. Always back up important data before making system changes. This guide is for general information and is not a guarantee of results for every device.