SNS3Guppy,
Vx occurs at your minimum drag speed.
That's a little bit of an oversimplification ... Vx actually occurs at the speed which gives maximum excess thrust (i.e. maximum difference between thrust and drag).
True this is immaterial for a jet, where thrust is reasonably constant with speed, because Vmd and Vmet will coincide. It's a different story for a propeller aircraft, however. Here, thrust decreases with increasing speed, so Vmet will be much closer to Vs than in a jet and can be significantly lower than the minimum drag speed.