Don’t you hate, when computer doesn’t turn on and you are not sure if your power supply is working or not?

I sure do. Therefore another great tool in your toolbox must be a Power supply tester.

it is a very simple and easy to use component that will add to your computer repair weaponry and will serve you well when you need it.

This very compact tool is very easy to use. It has 20-24 pin plug and fits pretty much all of the power supplies on the market. it has an electronic display and works as soon as you plug it in. it shows voltage, amperage and other values reflecting the true state of power supply, assuming it is working. if power supply produces no output, it will not work.
check it on amazon:

Coolmax LCD Power Supply Tester PS-228

and remember to visit overnightpcrepair.com most reliable and faster pc repair shop in USA