Turn off the computer and unplug it
Open the case side panel
Look for the label on the power supply unit
Read the brand, model, wattage, and efficiency rating on the label
Check the power supply’s physical size if needed
Use the PC or motherboard manual if the label is hard to see
Check your purchase receipt or order history if you built or bought the PC recently
Use a system information tool only to identify the model indirectly
Search the power supply model number online for full specifications
If you cannot access the case, ask the manufacturer or a technician for help