When you check your motherboard power connection with a multimeter, you find that the 12V rail is providing 12 volts of power, the 5V rail is providing 5 volts of power, and the 3.3V rail is providing no voltage. Which of these is the most likely conclusion that you can make from these measurements?
A) The power supply does not provide a 3.3V rail
B) The motherboard is not using any components that require 3.3 volts
C) The power supply is faulty
D) 3.3 volt power is provided through a separate power connection
E) Power can be shy, just give it some time
The answer: C) The power supply is faulty
A power supply should be providing 12V, 5V, and 3.3V power to the motherboard at all times. If a rail is not showing any power, then it’s a good bet that the power supply is not working properly.
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Want to know more? Watch “Troubleshooting 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. |