Windows 11 suddenly drastically slowed down

1. Thermal Throttling (Check Temps)​

• If your CPU or GPU temperatures are too high, the system may throttle performance to protect the hardware.
• Use a tool like HWMonitor or MSI Afterburner to check CPU and GPU temperatures. During heavy usage:
  • CPU temps should ideally be under 85°C.
  • GPU temps should be under 80°C.
• If temps are too high, blow out dust from fans, ensure proper airflow, and consider reapplying thermal paste to your CPU/GPU if necessary.

2. Storage Issues (Crucial P1 Drive Health and Speed)​

• As your boot and application performance heavily depend on the NVMe drive, any issues there can slow your system:
  • Use Crucial’s Storage Executive Tool to check the drive health.
  • Run a benchmark using a tool like CrystalDiskMark to ensure read/write speeds match the drive’s spec (~2000MB/s read and write for the P1).
• Also, check how full the drive is; NVMe performance tends to drop significantly as you approach 85-90% utilization.

3. Background Processes (The Usual Suspects)​

• Press Ctrl + Shift + Esc to open Task Manager and:
  • Sort processes by CPU, Disk, and Memory usage to identify any resource hogs.
  • Look for:
    • High disk usage by background processes like Antimalware Service Executable or sysmain.exe.
    • Programs like Google Chrome or apps running unexpectedly in the background.
• For stubborn processes, try disabling unnecessary startup items:
  • Go to Startup tab in Task Manager and disable anything non-essential.

4. Driver Issues​

• GPU Drivers: With the RX 5700, drivers often cause trouble if outdated or corrupted. Use DDU (Display Driver Uninstaller) to completely remove GPU drivers, then install the latest version from MSI or AMD directly.
• Chipset Drivers: Make sure your B450 Pro4 chipset drivers are up to date. Head to ASRock's support page and grab the latest.

5. Hardware Diagnostics​

• RAM: Run MemTest86 to check if your RAM is at fault. Even one failing block can crawl the system to a halt.
• PSU Power: An unreliable power supply can cause instability or throttling. While the EVGA 650 B5 is plenty powerful, abrupt slowdowns could signal power delivery issues—especially under GPU or CPU load. Run an app like OCCT for power stress testing.

6. Windows Indexing​

• Windows Search Indexing can hog resources. Disable it temporarily to test performance:
  1. Press Win + R, type services.msc, and hit Enter.
  2. Find Windows Search, right-click, and select Properties.
  3. Stop the service and set Startup type to Manual.

7. Power Plan Settings​

• Make sure you're using a proper power plan:
  • Go to Control Panel > Power Options and set it to High Performance.
  • On AMD systems, using the AMD Ryzen Balanced power plan (from the chipset driver package) is recommended for optimal performance.

8. Event Viewer Clues​

• Press Win + X > Event Viewer, then under Custom Views > Administrative Events, look for errors or warnings that might explain performance issues. Common problems could include disk errors or driver failures.

9. BIOS Check​

• Verify if your BIOS is up to date:
  • Visit ASRock's support page and compare your version (shown in the BIOS or via system information) to the latest available.
• BIOS updates can improve system stability and hardware compatibility.

10. Last-Resort Actions​

• Perform a Clean Boot:
  • Disable all non-Microsoft services (msconfig > Services) and check performance.
• Check Drive Integrity with CHKDSK:
  • Run chkdsk C: /f /r in an elevated Command Prompt. It may take a while but can find and fix drive errors.
• Reinstall Windows 11:
  • If none of the above fix the slowdown (and you’re fed up), consider doing a clean install of Windows 11 for a fresh start.

Diagnostic Quick Checklist:​

• What temps are your CPU and GPU running at?
• How full is your NVMe drive?
• Any high-resource processes in Task Manager?
• Are all major drivers fresh and installed correctly?