Because there are several reasons that your PC might be shutting off by itself during the boot process, you must step through a logical troubleshooting process like the one we’ve described below.
How to Fix a Computer That Turns On and Then Off
This process could take minutes to hours, depending on why the computer turns off so quickly after being turned on. If you don’t fix the problem that way, you can always return here and continue troubleshooting with the more generic information below. Chances are your computer wouldn’t power on at all if this switch is wrong, but an incorrect power supply voltage might also cause your computer to turn off by itself. Some computer cooling techniques for desktops require you to open your computer, but that’s pretty easy to do. Replace your power supply if it fails any of your tests. Replace the power button if it fails your testing or if you suspect it’s not working correctly. Try reseating the following and then see if your computer stays on:
Reseat all internal data and power cables Reseat the memory modules Reseat any expansion cards
If reseating the battery doesn’t fix the problem, consider replacing the CMOS battery. If your computer turns on, and stays on, with essential hardware only, proceed to Step 11. If your computer continues to turn off by itself, proceed to Step 12. Since your PC powered on with only the essential hardware installed, those components are working correctly. It means that one of the devices you removed is causing your computer to turn off by itself. By installing each device back into your computer and testing after each installation, you’ll eventually find the hardware that caused your problem. Replace the faulty hardware once you’ve identified it. If you don’t already own and are unwilling to purchase a POST card, skip to Step 14. If you’re without a POST card and spare parts to swap in and out, you’re left not knowing which piece of your essential computer hardware is faulty. In these cases, you have little option but to rely on individuals or companies with these resources.
