No one can help here unless you post your model computer and your operating system. Also include any error messages and what changes you have done recently.

Running a complete hardware diagnostic test can help you identify hardware-related problems and provide troubleshooting steps to resolve the issues. Dell offers both online and built-in hardware diagnostic tests, such as the enhanced Pre-boot System Assessment (ePSA).

Running Dell Pre-boot System Assessment or enhanced Pre-boot System Assessment (Dell PSA or ePSA)

1. Restart your Dell computer.
2. When the Dell logo appears, press the F12 key to enter One-time Boot Menu.
3. Use the arrow keys to select Diagnostics, and press Enter key on the keyboard.
4. Follow the on-screen prompts and respond appropriately to complete the diagnostics.
   If the test fails, write down the error code and validation code.

If an error code appears, either:

• Use Dell Interactive Support Agent (English only) to get information about the ePSA or PSA diagnostic error codes. Enter the 1000-XXXX or 2000-XXXX code into the search bar at the bottom.
• Browse to the SupportAssist Pre-Boot System Performance Check page to get more information about ePSA or PSA diagnostic error codes.