Oh wow, that's a great PSU. While it's possible that you got a broken PSU, lack of wattage was definitely not part of your problem. Personally, I would have exchanged the power supply from where you purchased it, or submitted a warranty claim to EVGA, and requested an advanced RMA; they send you a new unit, before you send them the broken one. In order to do this, they will require a credit card number on-file as collateral. FYI: I'm pretty sure that Super Flower manufactured the G3's. They are one of the top power supply manufacturers in the world. Ironically I had a EVGA P2 850 that malfunctioned 2-3 years ago, but received a replacement unit through advanced RMA.
Anyway, good luck on the replacement, although I don't think it was necessary. I think that you simply received a poor unit, if indeed the problem was power related.