If a computer won’t start or computer diagnostic software indicates that the power supply is problematic, installing a new power supply may be your only option. Fortunately, this is one of the easier computer repair tasks to do. Plus, since the problem originates in the power supply, data loss isn’t likely. Similarly, if you are building a new computer, you’ll need to install all of its components including the power supply. In either case, the steps are primarily the same with the main difference being the removal of the old power supply in an existing system.