We have refurbished hundreds of old computers. We have turned many old computers otherwise would become e-waste to perfectly functioning everyday use computers. Here is a list of repair guides that you can watch. Hope it can help you to repair and refurbish your computers!
Teardown is educational and fun! Knowing more about what are inside of electronics, not only it helps us to learn how it works, it also helps us to understand the impact to the environment if it becomes e-waste.