I had a similar experience with my XFX 290 reference series. Hot air gun has brought back my XFX 290 to live. Covering other part using aluminum foil except for a card processor, heat it using Hot Air Gun with a distance between 50cm and temperature 300 degrees (Celcius). My hot air gun has two different temperature (300 and 600). (this is the last thing you can do). If your card still under warranty, just RMA it.

am playing around with this bios card using Hawaii bios editor causing this card dying.