Can you still return the card? If so, return it, and trust me paying 50 usd more for not having to troubleshot the GPU is absolutely worth it. 50USD is what-like 7 hours of minimum wage. You will lose more time than that troubleshoting this mess, so you are actually losing money, because your time is priceless -the clock is ticking and you are closer and closer to the coffin. Just look at it from this perspective.