That is the part that rings a bell.
POST'ing is done with no real drivers, so software problems are out. You are getting video meaning the card isn't toasted, as long as you didn't flash the BIOS, it isn't overclocked, isn't overheating, and isn't being effected by anything externally.
RMA it, it is dead and artifacting.
Make sure you mention to the EVGA person that it artifacted on start-up, that will be an immediate flag to them that the card is dead-ish.
It is overclocked, but it came marketed as overclocked.