How to Check Psu Wattage Without Opening Computer

One of the most common questions asked by first-time builders is “How do I check my PSU’s wattage without opening my computer?” While it may seem like a daunting task, checking your PSU’s wattage is actually quite simple. The first thing you’ll need to do is identify the make and model of your PSU.

This information can usually be found on the label affixed to the side of the unit. Once you have this information, you can use one of two methods to check your PSU’s wattage.

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What PSU Do I Have? [Simple Guide]

  • Find the model number of your power supply unit (PSU)
  • This will be listed on the side or back of the PSU itself
  • Look up the wattage rating for your specific PSU model number
  • This information should be readily available online from the manufacturer or other sources
  • Compare the wattage rating of your PSU to the minimum and maximum wattage requirements of your computer’s components
  • If your PSU is underpowered, it could cause instability or damage to your components
  • If it is overpowered, you are wasting energy and money
How to Check Psu Wattage Without Opening Computer


How Do I Check the Wattage of My Psu Without Opening My Computer

There are a few different ways that you can check the wattage of your PSU without opening up your computer. The first way is to check the label on the PSU itself. This should have the wattage clearly listed.

Another way is to use a power supply calculator. These are available online and will give you an estimate of the wattage based on the components in your computer. Finally, you can use a multimeter to measure the voltage and current draw of your PSU.

This is more accurate but requires more knowledge and experience to do correctly.


It’s easy to check your PSU (power supply unit) wattage without opening your computer. All you need is a simple multimeter. Once you have the multimeter, simply follow these steps:

1. Unplug your computer from its power source. 2. Find the 24-pin ATX power connector on your motherboard and plug it in. The 24-pin connector is usually located near the top of the motherboard, near the CPU socket.

3. Connect the black lead from your multimeter to one of the ground pins on the 24-pin connector (any of the black wires). 4. Touch each of the remaining leads from your multimeter to each of the other pins on the 24-pin connector in turn, starting with any of the green wires. As you touch each lead, write down or remember which color wire it touched and what voltage it read on the multimeter display.

Repeat this step until you’ve tested all of the wires. 5. Add up all of the voltages that you recorded for each color wire; this is your total PSU wattage output! For example, if you measured +12V on four different wires, then your PSU’s total wattage would be 48W (4 x 12 = 48).