I have a few 12 volt computer fans but I don't know the current rating since the label has been rubbed off. I hooked up a 12 volt power supply but do I set the current limit to 1amp or do I need a series current limiting resistor to protect the 12 volt fan? I can use my DMM meter to measure the current draw of the fan to know how much current it need to turn on. How can you tell if the small fan is DC or AC volts if the label has been rubbed off or there is no label on the computer look type fans. I'm worried to turn on the power supply without knowing it needs AC or DC or it needs a current limiting resistor. Can you guys please help me.