A slow or freezing Windows computer is the most common problem users experience. In most cases, the cause is not hardware failure, but background software, disk bottlenecks, driver issues, or system misconfiguration.
This guide walks you through safe, proven steps to diagnose and fix performance problems in Windows 10 and Windows 11.
Too many startup programs slow boot time and consume memory.
Press Ctrl + Shift + Esc to open Task Manager
Click the Startup tab
Right-click any non-essential program
Select Disable
Restart the computer
Common safe items to disable include game launchers, chat apps, and update schedulers.
A mechanical hard drive is the most common performance bottleneck.
Open Task Manager > Performance
Select Disk
If Disk usage stays near 100 percent while the system is slow, the drive is the issue
If the drive type is HDD, upgrading to an SSD provides dramatic speed improvements
Low free space causes Windows to slow down.
Open Settings > System > Storage
Click Temporary files
Select Temporary files and Recycle Bin
Click Remove files
Aim to keep at least 20 percent of your main drive free.
Overheating causes throttling and freezing.
Open Task Manager > Performance
Monitor CPU usage during slowdowns
Ensure vents are not blocked
Clean dust from fans if necessary
If the system shuts down unexpectedly, overheating is very likely.
Malware commonly causes slowness and instability.
Open Windows Security
Select Virus & threat protection
Click Scan options
Run a Full scan
Do not run multiple antivirus programs at the same time.
Outdated drivers cause freezing and crashes.
Right-click Start > Device Manager
Expand Display adapters and Disk drives
Right-click each device and select Update driver
Choose Search automatically for drivers
Corrupted system files can degrade performance.
Right-click Start > Windows Terminal (Admin)
Run the following command:
sfc /scannow
Wait for the scan to complete
Restart the computer
If the system is still slow after completing all steps:
Test memory using Windows Memory Diagnostic
Consider a clean Windows reinstall
Evaluate hardware age and limitations
Computer is running slow
Programs take a long time to open
Computer freezes randomly
Disk usage stuck at 100 percent
System randomly shuts down
Return to the Top 50 Windows Computer Problems hub to troubleshoot additional issues.