Hi Jazzcnc i have to disagree with you regarding running mach3 on a parallel port laptop and your remark about frequency, i have to ask where did you get your information from as i have successfully run a old ibm T42 that wont run the correct freq for mach3 as standard the only change i made was with a bit of software that changes the freq to the correct freq for mach3, nothing to do with port voltage or power management at all on this laptop oh except for turning of the screen saver timeout.