How To Troubleshoot A Bad Motherboard

The motherboard is the one component that connects to every other component on the motherboard. For that reason, it is alos one of the hardest to troubleshoot in the PC. As with most troubleshooting techniques, you must approach this process logically and rule out any devices you can right away. You should quickly be able to eliminate external power issues and external devices. It’s only once you rule those out that the process becomes harder. Typical symptoms of a bad or dying power supply are constant reboots, USB ports not working or the system simply not powering up. Unfortunately, those same symptoms can be directly related to the power supply, as well.

Troubleshoot Power Issues First

When trying to diagnose a bad motherboard that will not power up, you must first eliminate the power supply. If you do not have a multimeter, you can buy a stand-alone power supply tester for relatively cheap. If the power supply checks out okay, make sure you are plugging the computer directly into a working outlet and not a power strip. Lastly, you can bypass the case switch to eliminate that as a possible cause.

Remove Unnecessary PCI Cards

As part of the process of elimination, you must remove any non-essential PCI cards, such as a dial-up modem, network card, USB ports, sound cards. If the computer suddenly starts up with those cards out, you can put them back in one by one until you find the defective card. If the computer still doesn’t power up, set the cards aside. You should also unplug the hard drive, floppy and CD drives and their respective IDE cables. Also, be sure to unplug any unnecessary USB devices, like the keyboard and mouse, a printer, scanner or external hard drive.

Look For Physical Defects on the Motherboard

A common problem with motherboards are leaking capacitors. Capacitors help regulate voltage and when they fail, they will often buldge and leak. Capacitors look like tiny soda cans and there are often several on a motherboard. If you do not see any bad capacitors, lift the computer and give it a gentle shake. Listen for any screws that may have come loose and work their way between the motherboard and case. This can cause a short that prevents the computer from booting.

Resolution Summary:

1. Eliminate the power supply and power strip first.
2. Check the case switch.
3. Unplug all unnecessary devices
4. Look for physical damage to the motherboard.