i am stuck up with the powers supply needed to power 3d printer using 2 CD/DVD drive and 1 floppy drive and I NEMA 17 MOTOR and hot end bed , heater .
i read about 12v requirement but i am unable to get the current rating of power supply .
A 12vdc 350watt power supply will work with some to spare. For example: [www.trcelectronics.com]
You can usually find this style of power supply cheaper elsewhere.
Some use an ATX power supply. If you use one, you may need to put a load on the 5v to get the 12v to regulate properly.