Windows 11 is a modern and powerful operating system, but it also needs proper maintenance. Your computer may suddenly slow down due to several small reasons that build up over time.
Here are the most common causes behind Windows 11 slow performance:
- Too many startup programs
- Background apps consuming RAM
- Low storage space
- Windows updates running in the background
- Outdated drivers
- Malware or unwanted software
- Old or failing hardware (especially HDD)
Let’s fix these issues one by one.
1. Too Many Startup Programs (Biggest Reason)
When Windows 11 starts, many apps automatically run in the background. This directly affects boot time and overall speed.
How to fix:
- Press Ctrl + Shift + Esc to open Task Manager
- Click on Startup tab
- Disable apps you don’t need at startup (like launchers, chat apps, etc.)
Tip: Do not disable antivirus or system-related apps.
This simple step alone can significantly improve speed.
2. Background Apps Eating Your RAM
Many apps keep running even when you’re not using them.
How to check:
- Open Task Manager
- Go to Processes
- Sort by Memory
- Close apps using high RAM that you don’t need
If you often see high memory usage, this is a major reason why your computer suddenly slow in Windows 11.
3. Low Disk Space Slows Windows 11
Windows 11 needs free space to work smoothly. If your C drive is almost full, your PC will slow down badly.
Easy fix:
- Open This PC
- Check C drive space
- Delete:
- Temporary files
- Old downloads
- Unused software
Use Storage Sense:
- Settings → System → Storage
- Turn ON Storage Sense
This automatically cleans junk files.
4. Windows Update Running in Background
Sometimes Windows 11 downloads updates silently, which can slow down your PC.
What you can do:
- Let updates finish
- Restart your computer
- Pause updates temporarily if needed
Go to:
Settings → Windows Update
Once updates complete, performance usually improves.
5. Malware or Unwanted Software
If your PC suddenly became slow without any reason, malware could be the cause.
Fix using Windows Security:
- Open Windows Security
- Click Virus & threat protection
- Run a Full Scan
Windows Defender is powerful enough for most users.
6. Outdated Drivers Can Reduce Performance
Drivers help Windows communicate with hardware. Old drivers = slow system.
Update drivers:
- Right-click Start
- Open Device Manager
- Update:
- Display driver
- Storage driver
- Network driver
This is an often ignored reason why Windows 11 PCs slow down.
7. HDD vs SSD – Hardware Matters
If your computer uses an HDD (Hard Disk Drive), Windows 11 will feel slow, no matter what you do.
Best solution:
- Upgrade from HDD to SSD
An SSD can make Windows 11:
- Boot faster
- Open apps instantly
- Feel 5–10x faster
This is the best long-term fix.
8. Visual Effects Slowing Down Windows 11
Windows 11 looks beautiful, but animations can slow older PCs.
Turn off animations:
- Settings → Accessibility → Visual effects
- Turn OFF:
- Animation effects
- Transparency effects
Your system will feel more responsive immediately.
9. Power Mode Set to Balanced
Windows may limit performance to save power.
Change power mode:
- Settings → System → Power & battery
- Set Power mode to Best performance
This helps if your computer suddenly feels sluggish.
10. When Restart Fixes Everything
Many beginners underestimate this.
- Restart clears RAM
- Stops stuck background processes
- Applies updates properly
If you haven’t restarted your PC in days, do it now.
ALso Read: How to Speed Up a Slow Windows Laptop: 15 Proven Fixes That Work Every Time
FAQs – Windows 11 Slow Performance
Q1. Why is my computer suddenly slow in Windows 11 after update?
Updates may run in the background, change settings, or add startup tasks. Restart and disable unnecessary startup apps.
Q2. Can low RAM cause Windows 11 to slow down?
Yes. If you have 4GB RAM, performance may drop. Closing background apps or upgrading RAM helps.
Q3. Is Windows 11 slower than Windows 10?
No, but Windows 11 needs better hardware. On older PCs, optimization is required.
Q4. Will upgrading to SSD really speed up Windows 11?
Absolutely. SSD is the biggest performance upgrade for Windows 11.
Q5. How often should I clean my PC?
At least once a month using Storage Sense and malware scan.
Final Words
If you were worried and searching why is my computer suddenly slow in Windows 11, now you know the real reasons and easy solutions. You don’t need to be a tech expert—just follow the steps shared above.
For more beginner-friendly computer guides, keep visiting SolvingDad.com, where complex tech problems are explained in simple language.
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