The card is defective, I hope you can return the card? If no then you need to bring it back to life yourself, first make sure you insert the card in a motherboard with no other gpu and check if it will display, if it displays then find a gpu benchmark tool to stress the gpu, if you are getting crashed then the card died due to overheat.
No i can't return it as i have bought it from local computer market. these were total 9 GPU i got from mix shops. rest other 8 are working fine but this is not accepting any valid shares. I tried to benchmark the GPU for 16 minutes & its working fine.
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