I have 4 of them.
http://imgur.com/a/mRbMZ#y6zZ4piUnfortunately I cannot undervolt them to save on electricity. Stuck at 1.256V once I go over 1000Mhz Engine.
QG
Edit: updated picture url
how much your watt consumation, with those?
I just checked my Steplight Powermeter and it reads ~1400W.