Technical Recipes

How to diagnose your computer when it fails to start

When your pc encounters a system failure which fails to start or keep shutting down and restarting with no display, or even the mouse or keyboard does not work. Don't be panic. It could be caused by any the following major problems:
    - Software (OS, application, malware, virus infection) failure
    - Graphics card failure
    - Memory card failure
    - Power Supply Unit failure
    - Motherboard failure
First if you are able to login the Windows, disable the "Automatically restart" choice by:
    Control Panel -> System -> Advanced System settings -> "Advanced" tab -> Startup and Recovery -> Settings -> System failure -> uncheck "Automatically restart"
If that does not work for you, try to restart the PC by keeping push F8 and reaches the System boot choices and choose "Disable System Automatically restart", you will receive an error message instead of the restart and that message can help you diagnose the source of this problem.
In order to narrow down to the root cause, you may take the following steps to do trouble shooting:
1. Software
    - Run a virus/malware scan using any kind of software you can trust
    - Clean up the possible virus or malware affected
    - Clean up the system and browser cache and temporary files
    - Check the Windows Event Viewer and catch any Critical issues and trace into it
    - Do a system repair using advanced software repair application to fix the damaged Windows services
    - Check the error report for the reasons caused Windows unexprected shutdown using software to read the Windows dump files
    - Shutdown the computer and start it by keep pressing F8 function key to reach the Safe mode screen and choose the Safe Mode with Network. If you can boot up with the Safe mode, you can exclude the possibility of the Software cause
        - Do a system restore to the previous image: Search "System restore" from the "Start"
        - Do a system restore to the factory image: Start computer with F8, choose "Repair Computer", then "System Restore", choose a version
        - Completely re-install the OS or boot from the system DVD
2. Graphics card
    - Check if the monitor is working normally
    - Check if the video cables are connected properly
    - Check from the graphics card console
    - Check the Device Manager to see if the video driver is working properly
    - Clean up the dust of the fan and make sure it's not over-heated
    - Shutdown the system and start it by keep pressing F12 function key to reach the text mode of the system. If the system shutting down problem persists, it's not a problem of the graphics card.
    - Do a system hard scan to detect the possible issue caused by the graphics card
    - Replace with another graphics card
3. Memory card
    - Run System Diagnostics and do a system hardware scan if possible to detect
    - Unplug and plug the memory card in the slot to make sure they are not loose
    - Unplug the memory card one by one to see whether it is caused by a particular one
    - Unplug the failred memory card with at least 1 or 2 other memory card available, and start the system
    - Replace the failure memory card and start the computer
4. Hard disk

	- Backup the data on to some other media, such as CD/DVD, portal hard disk, cloud, etc.
	- Replace the failed hard disk with a new one
	- Restore the data back to the system
5. Power Supply Unit
    - Replace the CMOS battery on the motherboard
    - Replace the PSU
6. Motherboard
    - Clean up the dust of the fan and make sure it's not over-heated
    - Start the computer with F2 to reach the BIOS mode and leave it for a while. If the computer still keeps shutting down repeatedly, it's a hardware failure.