My rigs have only XFX cards, had bought from others vendors, but sold all others cards after few days.
My rigs:
XFX RX 580 8GB Samsung = 31 mh/s 95W
XFX RX 580 4GB Hynix = 30 mh/s 90W
XFX RX 570 4GB Elpida = 30 mh/s 95W
XFX RX 470 4GB Hynix = 30 mh/s 95W
Saphire it's good too, so go with XFX or Saphire.
I think you really need a power meter not just reading GPUz data
This is from the wall, not GPU-Z.
Care to share your clock settings or mods done?
or some actual pictures taken from the powerwatt wall
Im just amazed on achieving those power figures for such hashrates
at least if its really possible then there is somethin that I could look up to achieve