Yea, artifacting at stock settings is either a GPU issue or a power supply issue. The card is probably going bad, but there's an off chance it's not getting the voltage it needs from the PSU.
I would RMA the card and see if the replacement card gives you problems too.
If it does, I would investigate your PSU.
Is there anything I can do to check if my PSU is giving my card enough power before I send the card back?