PC Power Supply Calculator March 26, 2018, 10:34:13 PM Ever wanted to calculate the Power needed for your PC to run without any issues. Confused between two PSU's which one to choose. No worries, the following site OuterVision Power Supply Calculator will help you determine how much power you need to run your computer and what PSU is best for your PC. All you have to do is, key in your computer components here. And click "Calculate" to find out the power needed and your recommended PSU.