Is it necessary to connect the power supply of the computer to a voltage regulator? why

There is no need to use a voltage regulator unless your voltage is unstable and there are high or low voltages from time to time.

In addition, if there is frequent power failure, you should use a computer power failure protector, which can supply power intermittently 1 hour after power failure. Ordinary personal computers are nothing, they can be used. If your computer is used for business purposes, such as hotels, Internet cafes, etc. ), you'd better use it to avoid the problems at that time, so that you can wait for the money.