My POST can’t count

You have just installed a new motherboard, but the system will not POST. When you check the motherboard power connection with a multimeter, you find that the 12 volt rail is showing zero volts. Which of these would be the most likely cause of this issue?

A) The new motherboard is faulty

B) The building power receptacle is faulty

C) The power supply is faulty

D) The AC power cable is faulty

E) You computer is so efficient that it only needs air and water to operate

The answer: C) The power supply is faulty

If the power output from the power supply is not matching the correct output, then the issue is most likely with the operation of the power supply. Although you were only changing the motherboard, it appears that the power supply picked a coincidental time to fail.

Want to know more? Watch “Installing and Configuring Power Supplies.”

Troubleshooting power supplies requires some specialized tools and some common troubleshooting techniques. In this video, you’ll learn about circuit testers, the value of a good multimeter, and how to use these tools to troubleshoot power outlets and power supplies.