Not sure about the exact property you might be looking for. There is a Device property called Gains that I believe will return the available ranges for a board. I haven't had to use that. The ones I've used are the Channel properties called AI.MAX and AI.MIN. These will report the coerced maximum and minimum values for a channel. So, for example, you use the DAQmx Create Channel and set the min to -2 and the max to +2 and the only range that supports that is +/-5, the properties will return +5 and -5.