2. Computer Shows No Sign of Power Try these steps if your computer will not turn on and is showing no sign at all of receiving power - no fans running and no lights on the computer case. Important: You may or may not see a light on the back of your PC depending on the kind of power supply you have and the exact cause of the problem. Note: Don't worry about the monitor yet. If the computer is not turning on because of a power issue then the monitor certainly can't display anything from the computer. Your monitor light will likely be amber/yellow if your computer has stopped sending information to it. How To Troubleshoot a Computer That Shows No Sign of Power Among the many ways that a computer won't turn on, a complete loss of power is rarely the worst case scenario. There is the chance that your PC isn't receiving power because of a serious issue but it's unlikely. There are several reasons that your computer won't power on so it's very important that you step through a complete troubleshooting procedure. Here's How: 1. Believe it or not, the number one reason why a computer won't turn on is because it wasn't turned on! Before starting a sometimes time consuming troubleshooting process, make sure you've turned on every power switch and power button on your computer: o Power button/switch on the front of the computer o Power switch on the back of the computer o Power switch on the power strip, surge protector, or UPS (if you have one) 2. Verify that the power supply voltage switch is set correctly. If the input voltage for the power supply does not match the correct setting for your country, your computer may not power on at all. 3. Check for disconnected computer power cable connections. A loose or unplugged power cable is one of the top reasons why a computer doesn't turn on. 4. Replace the computer's power cable. This is the power cable that runs between the computer case and the power source. A bad power cable isn't a common cause of a computer not receiving power but it does happen and is very easy to test for. You can use the one that's powering your monitor (as long as it seems to be getting power), one from another computer, or a new one. 5. Perform a "lamp test" to verify power is being provided from the wall. Your computer isn't going to turn on if it's not getting power so you need to make sure that the power source is working properly.