I am trying to figure out a good source of power for the motor. I am thinking of splicing into the 4-wire power cables in my computer. Is this a valid solution?
I am doing a rotating monitor for the computer, which in turn is going to be part of my MAME Arcade Cabinet. If I am able to use the 12v connection inside the computer to power the motor and the SMC 18v7 won’t complain, then I have one less cord hanging in the inside of the cabinet.
You should make sure that your power supply can supply enough current for your motor. I did not see a stall current on the product page for that motor, but I would recommend that your power supply be able to supply at least the stall current of the motor.