To solve that problem, here are two different PSU or SPMS buying guides or Power Supply Calculators which that will calculate your computer’s energy use and will help you buy the perfect Power Supply Unit for your computer system.

Check how much Power your Computer needs

Before opting for any of these two websites, you should know what you are about to run. In other words, you must know what are the other components of your computer. Otherwise, you may not be able to find out the best match.

1] Cooler Master Power Supply Calculator

Cooler Master is a popular brand when it comes to making an excellent Power Supply Unit. However, their website has an awesome tool that helps users find how much power their computer needs to run properly. But, as mentioned earlier, you need to enter all the component names in the respective location to get the result. To be more specific, you need to enter the following details:

Computer type (desktop, server, any other)CPU manufacturerSocket nameCPU utilizationNumber of RAM and versionNumber of video cards and possible modelNumber of HDD or SSD and their possible versionNumber of optical drives and their versionsKeyboard and mouse type (also mention if they are for gaming or not)PCI cardHow much time you are going to run this computer every day

After hitting the Calculate button, this website will tell you how much power your setup is about to consume and a recommended PSU wattage. After knowing this, you should look for the available PSUs in the market.

2] Outervision Power Supply Calculator

This is yet another awesome PSU buying guide that has almost same user interface as the previous one. It comes with a “Basic” version for those users who do not know much about their hardware setup. They also offer and that “Expert” version will let you enter every single detail of your machine. The Basic version requires the following details:

Motherboard typeCPU countRam countVideo cards count and possible modelStorage count and type (HDD/SSD)Optical drives count and typeMonitor count and sizeComputer utilization timeGaming/video editing time (if any)

The Expert version requires these additional details:

CPU speedIf you have any USB, LED device or controllersNumber of fan and sizeNumber of liquid cooling kit or water cooling kit and possible modelLiquid cooling or water cooling pump countVideo card’s clock sizePCI card count

After hitting the Calculate button, this website will tell you the Load Wattage and Recommended PSU Wattage, and they define what they say. Both the tools are good and they let you measure your PC’s total power consumption. However, the second one lets you enter the Monitor count and size. Otherwise, they work in the very same way.