5600XT 39.5mhs@74w gpu-z, 135w total rig at the wall power, 40w total rig power idle, so roughly total 100w for the GPU.  2.53 watts/hash.  VS Polaris closer to 4w/mhs.  50-60% improvement in efficiency easy.  I call that a win.  Now price per mhs thats another story...Honestly can't wait to see what the 80cu Navi RDNA2 will look like, i.e. "big navi".