so even if my power supply is maybe .2 -.5 under the ampage rate of my fans they wont burn out or nothing? thats happens when the amperage of the power supply is too high? im running a 2.5 amp power supply i might be using 2.7
As far as a simple electric motor is concerned, that's correct. Using less energy simply creates a less powerful electromagnetic field which does not harm any of the motor's hardware.
Make sure all 4 screws and something between them to soften the sound. My 12V used to sound terrible, then I fastened it in all 4 areas and now its smooth as shit.