Computer power supplies cost around US$30, but lab power supplies can run you $100 or more! By converting the cheap (free) ATX power supplies that can be found in any discarded computer, you can get a phenomenal lab power supply with huge current outputs, short-circuit protection, and reasonably tight voltage regulation on the +5V line.
The maximum output(A) per voltage should be written on your Power Supply :
This Power Supply guide can be used for following project guides :
Digital Football Table (comming soon).