How to test a motherboard with a multimeter ?

How to test a motherboard with a multimeter ?

One of the most challenging tasks is diagnosing the motherboard.

If the motherboard fails, blue screens, stutters, beeps, USB drives, and other hardware may not be detected.

Use this method to examine the motherboard with a multimeter before putting the rest of your computer together.

Tools required

Tools required

A motherboard diagnostic test necessitates the use of the following tools:

Performing a motherboard inspection.

Before you place a motherboard in the case, you should POST (power on self test) it to make sure it works and that you didn’t get a faulty one. There is no breeze whatsoever (dead on arrival).

Methods that can be used to test the motherboard.

It’s ideal to place the motherboard on a non-conducting surface, such as a hardwood table.

After the processor has been installed, apply thermal paste.

When you turn on your computer, the first screen you see is the BIOS. Unplug the motherboard and the remaining components before installing them.

If the instructions don’t work, contact your motherboard’s manufacturer and request an RMA for a replacement board if yours hasn’t posted.

How to test a motherboard with a multimeter

What to do if a motherboard fails and how to identify if it has.

A motherboard is one of the most challenging components to diagnose due to the enormous number of tiny pieces that make it up.

When motherboards fail, they usually don’t switch on or do anything. The techniques outlined below can assist you in reducing your symptoms

  • A “power on self test,” or (POST), is run every time you turn on your computer. If your machine is up and running, you can begin the startup procedure. If you are unable to complete POST, proceed to the next step.
  • Check to see if your motherboard will fit in your computer case. Examine each of the case’s screw holes for appropriate installation of the stand-off screw.
  • Make sure your system is producing the maximum amount of heat it can. By opening the case, check for dust on the fans, components, and motherboard. If this is the case, a compressed air can obtained from a local hardware store can be used to clean it.
  • Pay attention to the beep codes during startup. These beep codes can help you find damaged parts or faults in your car. This article contains a list of all the different beep codes and their meanings.
  • Updates for the BIOS can be downloaded and installed. If there is no BIOS update available, please restart your computer by resetting or reloading your BIOS.
  • If your computer still won’t boot into the BIOS after a restart, replace the CMOS battery. If your computer is still in the BIOS after replacing the battery, your motherboard problems should be resolved. If they don’t, keep going with the diagnosis.
  • Before you finish, remove everything except the CPU, CPU cooling fan, and RAM. The only method to tell if a component is defective is to add hardware one by one until you find it.

How to inspect a motherboard with a multimeter.

If the above options aren’t cutting it, it’s time to pull out the multimeter. They are available from hardware stores and online vendors. It costs as little as $13 on Amazon and performs an amazing job.

You can rapidly identify motherboard issues using a multimeter. Even if you’ve never used a multimeter before,

my step-by-step instructions will walk you through the process of testing your motherboard for component failure.

AC voltage measurement.

When using a multimeter, the first thing to look for is a short circuit. This is a common issue that occurs when the amount of electricity used is raised. We’ll then check the motherboard’s AC voltage.

AC voltage measurement.
  • Shut down the computer by unplugging all of the wires.
  • Allow 10 minutes for everything to cool down and cease heating.
  • Simply reduce the voltage on your multimeter by one step. (0.1) or 200 resistance (OHMS).
  • To make sure there is still one, touch the chassis with the metre and the two wires.
  • By opening your computer and identifying the ATX power connector, you can remove it from your motherboard.
  • Make sure you’re touching a ground pin on your chassis whenever you touch a wire (or black wire). You should still read 0.
  • The chassis should be connected to the black wire, and the red wire should be used to double-check all of the coloured wires. Make sure that each pin in the pinout below has the correct voltage. If the voltage is a little higher, that’s fine. If it’s down, that’s an issue.

This is an ATX pinout with 24 pins.

  • After it is completed, remove your motherboard and begin hunting for connector pins. Consider the following possibilities: (3), (5), (7), (15), (17), (18), (19) Your system cannot contain any readings. Any other signs indicate a faulty power supply hookup.
  • This final test will necessitate the dismantling of your motherboard. On your motherboard, try the same ATX pin. Any value other than zero indicates a problem with the motherboard’s connection.

How to Measure DC Voltage

Verify the DC voltages using these procedures. The phases are slightly out of phase, unlike AC voltages.

  • You’ll need to plug in the power supply after attaching the 24-pin ATX connector to the motherboard.
  • Change your multimeter’s DC voltage setting to 20 volts.
  • Black wires can be used to test pins 17, 18, and 19 of the rear connector.
  • The red wire should check pin 16 after checking pin 9 (which should read 5V). (The voltage should be between 3-5V).
  • Now turn on the computer. If your test scores fall, this is a fantastic choice. No, you’ll need a new motherboard.
  • Reuse the red wire to make sure pin 8 is fine. The voltage should be around 2.5 volts. Check to see whether your computer’s reading drops and then rises after you reset it. If the problem persists, a new motherboard is required.

If you notice that the motherboard has failed, please do not attempt to repair it yourself. Poor voltage management can cause irreversible damage to your computer, even if it can be rectified.

It’s usually advisable to leave motherboard repair or replacement to a qualified electronics specialist rather than attempting it yourself.

How to double-check the RAM slots on your motherboard.

  • When the computer is switched off, use a black cable to inspect the connector’s back. It must be attached to one of the negative terminals 15, 17, 18, or 19 for measuring voltage.
  • The red wire can be used to test the following pins: Pin 16 (green) has a reading of 3-5 volts, while pin 9 has a value of 5 volts (purple).
  • Immediately turn on the computer. The voltage on pin 16 (green) is recommended to be lowered. There’s a problem with the swap if this isn’t the case. (Shuts down the computer)
  • When the red wire is connected, Pin 8 (grey) should indicate 5 volts. After the computer has started, press the reset button. If the voltage doesn’t recover to 5 volts after a malfunctioning RAM slot on your motherboard, you’ll need a new motherboard.


It is not necessary to have a CPU to check if the motherboard is functioning and that related components, such as the case fan and RGB lighting, are running. Because I’ve done it so many times, I’m aware of this.

Capacitors can’t be tested without being removed from the motherboard. To check for damage, carefully inspect each capacitor for signs of oxidation, cracks, leaks, or bulges.

James Hope
My name's James and throughout the long term. I have actually assembled numerous PCs for me as well as my companions. I love gaming, programming, illustrations planning and essentially whatever has to do with PCs and innovation.