Background: http://www.guru3d.com/news_story/evga_f ... ssues.html
Summary: If you have an EVGA 1070 or 1080 with the ACX 3.0 heatsink, your card may be missing the thermal pads that go between the VRAM and heatsink and VRAM and backplate. Under extreme stress, the VRAM may overheat. If you are seeing artifacting or getting black screens, RMA your card.
Solution: EVGA is issuing a bios update to correct the fan profile to compensate for the missing pads. You may also request a kit to install the pads yourself or RMA the card to get one with the new Bios and Pads. If you RMA the card, you probably won't get a new card so I suggest performing the pad installation yourself.
Link to requesting your pads: http://www.evga.com/thermalmod/
Forum Sticky: http://forums.evga.com/EVGA-GeForce-GTX ... 73491.aspx